BACKGROUND: Malaria transmission in Sierra Leone is intense and perennial, accounting for 40% of clinical consultations. Medical workers diagnose suspected malaria cases using rapid diagnostic tests (RDT) and microscopy, with facility-level results reported to the Health Management Information System (HMIS) as monthly aggregates. Commodity stocks are reported to the Logistics Management Information System (LMIS). Partners investigated a striking increase in confirmed malaria during May-July 2023 in Sierra Leone, peaking in June to 46% above the June 2018-2022 mean. METHODS: The team first analysed national, district, and facility HMIS/LMIS data for RDT stocks, testing rates, and confirmed cases during January 2018-October 2023. Epidemic thresholds, defined as case counts two standard deviations (σ) above the previous 5 years' monthly mean, were assessed. Then four facilities in two districts were visited to interview staff. Lastly, the team reanalysed LMIS RDT stock data for all facilities in Sierra Leone using R to categorize their stock status by month. RESULTS: National epidemic thresholds were surpassed in May (2.56σ) and June (4.81σ) 2023. Twelve of sixteen districts surpassed epidemic thresholds during May-June. Investigation revealed inconsistent RDT distribution to facilities over time. National RDT distribution spiked in May 2023, when 551,888 RDT test kits were delivered. This was substantially larger than the 2019-2022 mean for May (53,121, 1,000% increase) and all months (126,866, 435% increase). Subsequently in June 2023, 386,343 tests were performed, 36% higher than the June 2018-2022 mean (285,123). Staff at all four visited facilities reported recurrent RDT stockouts. The proportion of facilities in Sierra Leone reporting positive RDT stocks at both the start and end of the month increased from 14% in April to 74% in June. 51% of facilities began May with RDT stockout and received RDTs that month. CONCLUSIONS: The 2023 spike in confirmed malaria was likely related to increased testing following an unusually large distribution of RDTs. Fluctuations in RDT availability impede the ability to recognize true case variations. Sierra Leone and its partners can strengthen supply chain logistics and health commodity stock tracking to ensure a consistent supply of RDTs and improve interpretation of surveillance data.

OBJECTIVES: World Health Organization issued Joint Statement on Data Protection and Privacy in the COVID-19 Response stating that collection of vast amounts of personal data may potentially lead to the infringement of fundamental human rights and freedoms. The Organization for Economic Cooperation and Development called on national governments to adhere to the international principles for data security and confidentiality. This paper describes the methods used to assist the Ministry of Health in bringing awareness of the data ownership, confidentiality and security principles to COVID-19 responders. METHODS: The Sierra Leone Epidemiological Data (SLED) Team data managers conducted training for groups of COVID-19 responders. Training included presentations on data confidentiality, information disclosure, physical and electronic data security, and cyber-security; and interactive discussion of real-life scenarios. A game of Jeopardy was created to test the participant's knowledge. RESULTS: This paper describes the methods used by the SLED Team to bring awareness of the DOCS principles to more than 2,500 COVID-19 responders. CONCLUSION: Similar efforts may benefit other countries where the knowledge, resources, and governing rules for protection of personal data are limited.

BACKGROUND: Hepatitis B virus (HBV) and neonatal tetanus infections remain endemic in Nigeria despite the availability of safe, effective vaccines. We aimed to determine health facilities' capacity for hepatitis B vaccine birth dose (HepB-BD) and maternal tetanus-diphtheria (Td) vaccination and to assess knowledge, attitudes, and practices of HepB-BD and maternal Td vaccine administration among health facility staff in Nigeria. MATERIALS AND METHODS: This was a cross-sectional study assessing public primary and secondary health facilities in Adamawa and Enugu States. A multistage sampling approach was used to select 40 facilities and 79 health-care workers (HCWs) from each state. A structured facility assessment tool and standardized questionnaire evaluated facility characteristics and HCW knowledge, attitudes, and practices related to HepB-BD and maternal Td vaccination. Frequencies and proportions were reported as descriptive statistics. RESULTS: The survey of 80 facilities revealed that 73.8% implemented HepB-BD and maternal Td vaccination policies. HepB-BD was administered within 24 h of birth at 61.3% of facilities and at all times at 57.5%. However, administration seldom occurred in labor and delivery (35%) or maternity wards (16.3%). Nearly half of the facilities (46.3%) had HCWs believing there were contraindications to HepB-BD vaccination. Among 158 HCWs, 26.5% believed tetanus could be transmitted through unprotected sex, prevented by vaccination at birth (46.1%), or by avoiding sharing food and utensils. 65% of HCWs knew HBV infection had the worst outcome for newborns. CONCLUSIONS: The limited implementation of national policies on HepB-BD and maternal Td vaccination, coupled with knowledge gaps among HCWs, pose significant challenges to timely vaccination, necessitating interventions to address these gaps.

BACKGROUND: Nigeria has the largest number of children infected with hepatitis B virus (HBV) globally and has not yet achieved maternal and neonatal tetanus elimination. In Nigeria, maternal tetanus diphtheria (Td) vaccination is part of antenatal care and hepatitis B birth dose (HepB-BD) vaccination for newborns has been offered since 2004. We implemented interventions targeting healthcare workers (HCWs), community volunteers, and pregnant women attending antenatal care with the goal of improving timely (within 24 hours) HepB-BD vaccination among newborns and Td vaccination coverage among pregnant women. METHODS: We selected 80 public health facilities in Adamawa and Enugu states, with half intervention facilities and half control. Interventions included HCW and community volunteer trainings, engagement of pregnant women, and supportive supervision at facilities. Timely HepB-BD coverage and at least two doses of Td (Td2+) coverage were assessed at baseline before project implementation (January-June 2021) and at endline, one year after implementation (January-June 2022). We held focus group discussions at intervention facilities to discuss intervention strengths, challenges, and improvement opportunities. RESULTS: Compared to baseline, endline median vaccination coverage increased for timely HepB-BD from 2.6% to 61.8% and for Td2+ from 20.4% to 26.9% in intervention facilities (p < 0.05). In comparison, at endline in control facilities median vaccination coverage for timely HepB-BD was 7.9% (p < 0.0001) and Td2+ coverage was 22.2% (p = 0.14). Focus group discussions revealed that HCWs felt empowered to administer vaccination due to increased knowledge on hepatitis B and tetanus, pregnant women had increased knowledge that led to improved health seeking behaviors including Td vaccination, and transportation support was needed to reach those in far communities. CONCLUSION: Targeted interventions significantly increased timely HepB-BD and Td vaccination rates in intervention facilities. Continued support of these successful interventions could help Nigeria reach hepatitis B and maternal and neonatal tetanus elimination goals.

INTRODUCTION: Antimicrobial resistance (AMR) is a global public health concern and irrational use of antibiotics in hospitals is a key driver of AMR. Even though it is not preventable, antimicrobial stewardship (AMS) programmes will reduce or slow it down. Research evidence from Sierra Leone has demonstrated the high use of antibiotics in hospitals, but no study has assessed hospital AMS programmes and antibiotic use specifically among children. We conducted the first-ever study to assess the AMS programmes and antibiotics use in two tertiary hospitals in Sierra Leone. METHODS: This was a hospital-based cross-sectional survey using the World Health Organization (WHO) point prevalence survey (PPS) methodology. Data was collected from the medical records of eligible patients at the Ola During Children's Hospital (ODCH) and Makeni Regional Hospital (MRH) using the WHO PPS hospital questionnaire; and required data collection forms. The prescribed antibiotics were classified according to the WHO Access, Watch, and Reserve (AWaRe) classification. Ethics approval was obtained from the Sierra Leone Ethics and Scientific Review Committee. Statistical analysis was conducted using the SPSS version 22. RESULTS: Both ODCH and MRH did not have the required AMS infrastructure; policy and practice; and monitoring and feedback mechanisms to ensure rational antibiotic prescribing. Of the 150 patients included in the survey, 116 (77.3%) were admitted at ODCH and 34 (22.7%) to MRH, 77 (51.3%) were males and 73 (48.7%) were females. The mean age was 2 years (SD=3.5). The overall prevalence of antibiotic use was 84.7% (95% CI: 77.9% - 90.0%) and 77 (83.8%) of the children aged less than one year received an antibiotic. The proportion of males that received antibiotics was higher than that of females. Most (58, 47.2 %) of the patients received at least two antibiotics. The top five antibiotics prescribed were gentamycin (100, 27.4%), ceftriaxone (76, 20.3%), ampicillin (71, 19.5%), metronidazole (44, 12.1%), and cefotaxime (31, 8.5%). Community-acquired infections were the primary diagnoses for antibiotic prescription. CONCLUSION: The non-existence of AMS programmes might have contributed to the high use of antibiotics at ODCH and MRH. This has the potential to increase antibiotic selection pressure and in turn the AMR burden in the country. There is need to establish hospital AMS teams and train health workers on the rational use of antibiotics.

Tetanus remains a considerable cause of mortality among undervaccinated mothers and their infants following unhygienic deliveries, especially in low-income countries. Strategies of the maternal and neonatal tetanus elimination (MNTE) initiative, which targets 59 priority countries, include strengthening antenatal immunization of pregnant women with tetanus toxoid-containing vaccines (TTCVs); conducting TTCV supplementary immunization activities among women of reproductive age in high-risk districts; optimizing access to skilled birth attendants to ensure clean deliveries and umbilical cord care practices; and identifying and investigating suspected neonatal tetanus cases. This report updates a previous report and describes progress toward MNTE during 2000-2022. By December 2022, 47 (80%) of 59 priority countries were validated to have achieved MNTE. In 2022, among the 50 countries that reported coverage with ≥2 doses of TTCV among pregnant women, 16 (32%) reported coverage of ≥80%. In 2022, among 47 validated countries, 26 (55%) reported that ≥70% of births were assisted by skilled birth attendants. Reported neonatal tetanus cases worldwide decreased 89%, from 17,935 in 2000 to 1,995 in 2021; estimated neonatal tetanus deaths decreased 84%, from 46,898 to 7,719. However, the global disruption of routine immunization caused by the COVID-19 pandemic impeded MNTE progress. Since 2020, reported neonatal tetanus cases have increased in 18 (31%) priority countries. Integration of MNTE strategies into priority countries' national postpandemic immunization recovery activities is needed to achieve and sustain global elimination.

The Integrated Disease Surveillance and Response (IDSR) system was adopted by the Sierra Leone Ministry of Health (MOH) in 2008, which was based on paper-based tools for health data recording and reporting from health facilities to the national level. The Sierra Leone MoH introduced the implementation of electronic case-based disease surveillance reporting of immediately notifiable diseases. This study aimed to document and describe the experience of Sierra Leone in transforming her paper-based disease surveillance system into an electronic disease surveillance system. Retrospective mixed methods of qualitative and quantitative data were reviewed. Qualitative data was collected by reviewing surveillance technical reports, epidemiological bulletins, COVID-19, IDSR technical guidelines, Digital Health strategy, and DHIS2 documentation. Content and thematic data analysis were performed for the qualitative data, while Microsoft Excel and DHIS2 platform were used for the quantitative data analysis to document the experience of Sierra Leone in digitalizing its disease surveillance system. In early 2017, a web-based electronic Case-Based Disease Surveillance (eCBDS) for real-time reporting of immediately notifiable diseases and health threats was piloted using the District Health Information System 2 (DHIS2) software. The eCBDS, integrates case profile, laboratory, and final outcome data. All captured data and information are immediately accessible to users with the required credentials. The system can be accessed via a browser or an Android DHIS2 application. By 2021, there was a significant increase in the proportion of immediately notifiable cases reported through the facility-level electronic platform, and more than 80% of the cases reported through the weekly surveillance platform had case-based data in eCBDS. Case-based data from the platform is analyzed and disseminated to stakeholders for public health decision-making. Several outbreaks of Lassa fever, Measles, vaccine-derived Polio, and Anthrax have been tracked in real-time through the eCBDS.

BACKGROUND: Novel oral polio vaccine type 2 (nOPV2) has been used to interrupt circulating vaccine-derived poliovirus type 2 outbreaks following its WHO emergency use listing. This study reports data on the safety and immunogenicity of nOPV2 over two rounds of a campaign in The Gambia. METHODS: This observational cohort study collected baseline symptoms (vomiting, diarrhoea, irritability, reduced feeding, and reduced activity) and axillary temperature from children aged 6 weeks to 59 months in The Gambia before a series of two rounds of a nOPV2 campaign that took place on Nov 20-26, 2021, and March 19-22, 2022. Serum and stool samples were collected from a subset of the participants. The same symptoms were re-assessed during the week following each dose of nOPV2. Stool samples were collected on days 7 and 28, and serum was collected on day 28 following each dose. Adverse events, including adverse events of special interest, were documented for 28 days after each campaign round. Serum neutralising antibodies were measured by microneutralisation assay, and stool poliovirus excretion was measured by real-time RT-PCR. FINDINGS: Of the 5635 children eligible for the study, 5504 (97·7%) received at least one dose of nOPV2. There was no increase in axillary temperature or in any of the baseline symptoms following either rounds of the campaigns. There were no adverse events of special interest and no other safety signals of concern. Poliovirus type 2 seroconversion rates were 70% (95% CI 62 to 78; 87 of 124 children) following one dose of nOPV2 and 91% (85 to 95; 113 of 124 children) following two doses. Poliovirus excretion on day 7 was lower after the second round (162 of 459 samples; 35·3%, 95% CI 31·1 to 39·8) than after the first round (292 of 658 samples; 44·4%, 40·6 to 48·2) of the campaign (difference -9·1%; 95% CI -14·8 to -3·3), showing the induction of mucosal immunity. INTERPRETATION: In a campaign in west Africa, nOPV2 was well tolerated and safe. High rates of seroconversion and evidence of mucosal immunity support the licensure and WHO prequalification of this vaccine. FUNDING: Bill & Melinda Gates Foundation.

Surgical site infections (SSIs) are a major public health threat to the success of surgery. This study assessed changes in SSIs and use of antibiotics among caesarean section (CS) and herniorrhaphy patients at a regional hospital in Sierra Leone following operational research. This was a comparative before and after study using routine hospital data. The study included all the CS and herniorrhaphy patients who underwent surgery between two time periods. Of the seven recommendations made in the first study, only one concerning improving the hospital's records and information system was fully implemented. Three were partially implemented and three were not implemented. The study population in both studies showed similar socio-demographic characteristics. The use of postoperative antibiotics for herniorrhaphy in both studies remained the same, although a significant increase was found for both pre- and postoperative antibiotic use in the CS patients, 589/596 (98.8%) in 2023 and 417/599 (69.6%) in 2021 (p < 0.001). However, a significant decrease was observed in the overall incidence of SSIs, 22/777 (2.8%) in 2023 and 46/681 (6.7%) in 2021 (p < 0.001), and the incidence of SSIs among the CS patients, 15/596 (2.5%) in 2023 and 45/599 (7.5%) in 2021 (p < 0.001). The second study highlights the potential value of timely assessment of the implementation of recommendations following operational research.

Implementing infection prevention and control (IPC) programmes in line with the World Health Organization's (WHO) eight core components has been challenging in Sierra Leone. In 2021, a baseline study found that IPC compliance in three tertiary hospitals was sub-optimal. We aimed to measure the change in IPC compliance and describe recommended actions at these hospitals in 2023. This was a 'before and after' observational study using two routine cross-sectional assessments of IPC compliance using the WHO IPC Assessment Framework tool. IPC compliance was graded as inadequate (0-200), basic (201-400), intermediate (401-600), and advanced (601-800). The overall compliance scores for each hospital showed an improvement from 'Basic' in 2021 to 'Intermediate' in 2023, with a percentage increase in scores of 16.9%, 18.7%, and 26.9% in these hospitals. There was improved compliance in all core components, with the majority in the 'Intermediate' level for each hospital IPC programme. Recommended actions including the training of healthcare workers and revision of IPC guidelines were undertaken, but a dedicated IPC budget and healthcare-associated infection surveillance remained as gaps in 2023. Operational research is valuable in monitoring and improving IPC programme implementation. To reach the 'Advanced' level, these hospitals should establish a dedicated IPC budget and develop long-term implementation plans.

Background As of 26 March 2021, the Africa CDC had reported 4,159,055 cases of COVID-19 and 111,357 deaths among the 55 African Union Member States; however, no country has published a nationally representative serosurvey as of May 2021. Such data are vital for understanding the pandemic's progression on the continent, evaluating containment measures, and policy planning. Methods We conducted a cross-sectional, nationally representative, age-stratified serosurvey in Sierra Leone in March 2021 by randomly selecting 120 Enumeration Areas throughout the country and 10 randomly selected households in each of these. One to two persons per selected household were interviewed to collect information on socio-demographics, symptoms suggestive of COVID-19, exposure history to laboratory-confirmed COVID-19 cases, and history of COVID-19 illness. Capillary blood was collected by fingerstick, and blood samples were tested using the Hangzhou Biotest Biotech RightSign COVID-19 IgG/IgM Rapid Test Cassette. Total seroprevalence was was estimated after applying sampling weights. Findings The overall weighted seroprevalence was 2.6% (95% CI 1.9-3.4). This is 43 times higher than the reported number of cases. Rural seropositivity was 1.8% (95% CI 1.0-2.5), and urban seropositivity was 4.2% (95% CI 2.6-5.7). Interpretation Although overall seroprevalence was low compared to countries in Europe and the Americas (suggesting relatively successful containment in Sierra Leone), our findings indicate enormous underreporting of active cases. This has ramifications for the country's third wave (which started in June 2021), where the average number of daily reported cases was 87 by the end of the month: this could potentially be on the order of 3,700 actual infections, calling for stronger containment measures in a country with only 0.2% of people fully vaccinated. It may also reflect significant underreporting of incidence and mortality across the continent.

Nigeria is estimated to have the largest number of children worldwide, living with chronic hepatitis B virus (HBV) infection, the leading cause of liver cancer. Up to 90% of children infected at birth develop chronic HBV infection. A birth dose of the hepatitis B vaccine (HepB-BD) followed by at least two additional vaccine doses is recommended for prevention. This study assessed barriers and facilitators of HepB-BD administration and uptake, using structured interviews with healthcare providers and pregnant women in Adamawa and Enugu States, Nigeria. The Consolidated Framework for Implementation Sciences Research (CFIR) guided data collection and analysis. We interviewed 87 key informants (40 healthcare providers and 47 pregnant women) and created a codebook for data analysis. Codes were developed by reviewing the literature and reading a subsample of queries line-by-line. The overarching themes identified as barriers among healthcare providers were: the lack of hepatitis B knowledge, limited availability of HepB-BD to vaccination days only, misconceptions about HepB-BD vaccination, challenges in health facility staffing capacity, costs associated with vaccine transportation, and concerns related to vaccine wastage. Facilitators of timely HepB-BD vaccination included: vaccine availability, storage, and hospital births occurring during immunization days. Overarching themes identified as barriers among pregnant women were lack of hepatitis B knowledge, limited understanding of HepB-BD importance, and limited access to vaccines for births occurring outside of a health facility. Facilitators were high vaccine acceptance and willingness for their infants to receive HepB-BD if recommended by providers. Findings indicate the need for enhanced HepB-BD vaccination training for HCWs, educating pregnant women on HBV and the importance of timely HepB-BD, updating policies to enable HepB-BD administration within 24 hours of birth, expanding HepB-BD availability in public and private hospital maternity wards for all facility births, and outreach activities to reach home births.

Among pregnant women, anemia, a condition of low hemoglobin concentration, can increase risk for maternal and fetal morbidity and mortality, including premature delivery, and other adverse outcomes (1). Iron deficiency is a common cause of anemia, and during pregnancy, iron requirements increase (2). Surveillance of anemia during pregnancy in the United States is limited. The Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) Participant and Program Characteristics (PC) data provide an opportunity to establish national and WIC state agency-level* anemia surveillance for WIC participants. National and state agency anemia prevalences among pregnant WIC participants at enrollment were examined using 2008-2018 WIC-PC data. Across all 90 WIC agencies (50 states, the District of Columbia [DC], five territories, and 34 Indian Tribal Organizations), anemia prevalence among pregnant WIC participants at enrollment increased significantly, from 10.1% in 2008 to 11.4% in 2018 (13% increase). Anemia prevalence increased significantly in 36 (64%) of the 56 agencies in states, DC, and territories, and decreased significantly in 11 (20%). Prevalence of anemia overall and by pregnancy trimester were higher among non-Hispanic Black or African American (Black) women than among other racial or ethnic groups. Anemia prevalence was higher among women assessed during the third trimester of pregnancy than among those assessed during first or second trimesters. Routine anemia surveillance using WIC enrollment anemia data can identify groups at higher risk for iron deficiency. Findings from this report indicate that anemia continues to be a problem among low-income women and reinforces the importance of efforts that ensure these women have access to healthier, iron-rich foods before and during pregnancy. This includes ensuring that eligible women are enrolled in WIC early during pregnancy.

Maternal and neonatal tetanus (MNT)* remains a major cause of neonatal mortality with an 80%-100% case-fatality rate among insufficiently vaccinated mothers after unhygienic deliveries, especially in low-income countries (1). In 1989, the World Health Assembly endorsed elimination(†) of neonatal tetanus; the activity was relaunched in 1999 as the MNT elimination (MNTE)(§) initiative, targeting 59(¶) priority countries. MNTE strategies include 1) achieving ≥80% coverage with ≥2 doses of tetanus toxoid-containing vaccine (TTCV2+)** among women of reproductive age through routine and supplementary immunization activities (SIAs)(††) in high-risk districts,(§§) 2) achieving ≥70% of deliveries by a skilled birth attendant,(¶¶) and 3) implementing neonatal tetanus case-based surveillance (2). This report summarizes progress toward achieving and sustaining MNTE during 2000-2020 and updates a previous report (3). By December 2020, 52 (88%) of 59 priority countries had conducted TTCV SIAs. Globally, infants protected at birth*** against tetanus increased from 74% (2000) to 86% (2020), and deliveries assisted by a skilled birth attendant increased from 64% (2000-2006) to 83% (2014-2020). Reported neonatal tetanus cases worldwide decreased by 88%, from 17,935 (2000) to 2,229 (2020), and estimated deaths decreased by 92%, from 170,829 (2000) to 14,230 (2019).(†††) By December 2020, 47 (80%) of 59 priority countries were validated to have achieved MNTE, five of which conducted postvalidation assessments.(§§§) To achieve elimination in the 12 remaining countries and sustain elimination, innovation is needed, including integrating SIAs to cover multiple vaccine preventable diseases and implementing TTCV life course vaccination.

BACKGROUND: A rapid increase in circulating vaccine-derived poliovirus type 2 outbreaks, and the need to reserve inactivated poliovirus vaccine (IPV) for routine immunisation, has increased the value of fractional dose IPV (fIPV) as a measure to prevent acute flaccid paralysis. However, the intradermal route of administration has been viewed as prohibitive to outbreak response campaigns. We aimed to establish the immunogenicity and safety of administering intradermal fIPV with a disposable syringe jet injector (DSJI) or an intradermal adaptor (IDA) compared with standard administration with a BCG needle and syringe (N&S). METHODS: This pragmatic, non-inferiority trial was undertaken in a campaign setting in communities in The Gambia. Children aged 4-59 months without contraindication to vaccination were eligible. Children were not individually randomly assigned; instead, the vaccination teams were randomly assigned (1:1:1) to one of three administration methods. Parents and the field team were not masked, but laboratory personnel were masked. Baseline demographic and anthropometric data were collected from the participants. Public health officers experienced at intradermal immunisation, and nurses without experience, had 2 h of training on each of the administration methods before the campaign. Participants were vaccinated using the administration method in use by the vaccination team in their community. Poliovirus serum neutralising antibodies (SNA) were measured in children aged 24-59 months before and 4 weeks after vaccination. Adverse events and data on injection quality were collected from all participants. The primary outcome was the type 2 immune response rate (seroconversion in seronegative [SNA titre <8] children plus a 4-fold titre rise in seropositive children). Adjusted differences in the immune response between the DSJI or IDA group versus the N&S group were calculated with 97·5% CIs. A margin of -10% was used to define the non-inferiority of DSJI or IDA compared to N&S. Immunogenicity analysis was done per protocol. The trial is registered with ClinicalTrials.govNCT02967783 and has been completed. FINDINGS: Between Oct 28 and Dec 29, 2016, 3189 children aged 4-59 months were recruited, of whom 3170 were eligible. Over 3 days, 2720 children were vaccinated (N&S, 917; IDA, 874; and DSJI, 929). Among 992 children aged 25-59 months with a baseline SNA available, 90·1% (95% CI 86·1-92·9; 281/312) of those vaccinated using the DSJI had an immune response to type 2 compared with 93·8% (90·6-95·8; 331/353) of those vaccinated with N&S and 96·6% (94·0-98·0; 316/327) of those vaccinated with IDA. All (53/53) type 2 seronegative children seroconverted. For polio type 2, non-inferiority was shown for both the IDA (adjusted difference 0·7% [97·5% CI -3·3 to 4·7], unadjusted difference 2·9% [-0·9 to 6·8]) and DSJI (adjusted difference -3·3% [-8·3 to 1·5], unadjusted difference -3·7% [-8·7 to 1·1]) compared with N&S. Non-inferiority was shown for type 1 and 3 for the IDA and DSJI. Neither injection quality nor the training and experience of the vaccinators had an effect on immune response. No safety concerns were reported. INTERPRETATION: In a campaign, intradermal fIPV is safe and generates consistent immune responses that are not dependent on vaccinator experience or injection quality when administered using an N&S, DSJI, or IDA. Countries facing vaccine-derived poliovirus type 2 outbreaks should consider fIPV campaigns to boost population immunity and prevent cases of acute flaccid paralysis. FUNDING: World Health Organization and the Medical Research Council.

INTRODUCTION: As of 26 March 2021, the Africa Centres for Disease Control and Prevention had reported 4 159 055 cases of COVID-19 and 111 357 deaths among the 55 African Union member states; however, no country has published a nationally representative serosurvey as of October 2021. Such data are vital for understanding the pandemic's progression on the continent, evaluating containment measures, and policy planning. METHODS: We conducted a cross-sectional, nationally representative, age-stratified serosurvey in Sierra Leone in March 2021 by randomly selecting 120 Enumeration Areas throughout the country and 10 randomly selected households in each of these. One to two persons per selected household were interviewed to collect information on sociodemographics, symptoms suggestive of COVID-19, exposure history to laboratory-confirmed COVID-19 cases, and history of COVID-19 illness. Capillary blood was collected by fingerstick, and blood samples were tested using the Hangzhou Biotest Biotech RightSign COVID-19 IgG/IgM Rapid Test Cassette. Total seroprevalence was estimated after applying sampling weights. RESULTS: The overall weighted seroprevalence was 2.6% (95% CI 1.9% to 3.4%). This was 43 times higher than the reported number of cases. Rural seropositivity was 1.8% (95% CI 1.0% to 2.5%), and urban seropositivity was 4.2% (95% CI 2.6% to 5.7%). DISCUSSION: Overall seroprevalence was low compared with countries in Europe and the Americas (suggesting relatively successful containment in Sierra Leone). This has ramifications for the country's third wave (which started in June 2021), during which the average number of daily reported cases was 87 by the end of the month:this could potentially be on the order of 3700 actual infections per day, calling for stronger containment measures in a country with only 0.2% of people fully vaccinated. It may also reflect significant under-reporting of incidence and mortality across the continent.

Objectives: Anemia is defined by hemoglobin (Hb) lower than normal based on cutoffs specific to age and sex. Hb increases with elevation as a response to lower blood oxygen, thus adjusting Hb for elevation is necessary before applying cutoffs. Recent evidence among preschool-aged children (PSC) and reproductive-aged women (WRA) suggests current World Health Organization (WHO) recommended Hb elevation adjustments need updating. We examined the Hb and elevation association among school-age children (SAC) to confirm these findings. Methods: Biomarkers Reflecting Inflammation and Nutritional Determinants of Anemia (BRINDA) project data include SAC aged 5–14 years (n = 23,454; 53.5% female) with data on Hb and elevation (−6 to 3,834 meters, m) from 6 population-based surveys from 5 countries (Columbia, Ecuador, Malawi, Mexico, United Kingdom). Anemia was defined as Hb < 115 g/L for SAC < 12 years and < 120 g/L for SAC 12–14 years after elevation adjustments. Generalized linear models were used to assess the association between Hb and elevation, including controlling for inflammation-corrected iron and vitamin A deficiency. Hb adjustments for each 500 m increase in elevation from sea level are proposed and compared to current WHO recommendations and new proposed PSC and WRA adjustments. Results: Hb was positively associated with elevation. There was no sex interaction, and the association was robust to model specification. The association among SAC and the resulting Hb adjustments were consistent with PSC and WRA findings, suggesting current WHO recommendations may under-adjust Hb at lower elevation (500–2500 m) and over-adjust Hb at higher elevation (>3000 m). Anemia prevalence in SAC using new elevation adjustments increased by 0.7 (UK) to 14.1 (Malawi) percentage points relative to current WHO elevation adjustments. Conclusions: Results confirm current WHO recommended Hb elevation adjustments may need updating, and anemia prevalence in SAC may be higher than currently estimated. Findings will inform global guidelines on use of elevation-adjusted Hb for anemia assessment and possible need for intervention among SAC. Funding Sources: Bill & Melinda Gates Foundation, Centers for Disease Control and Prevention, Eunice Kennedy Shriver National Institute of Child Health and Human Development, HarvestPlus, and United States Agency for International Development.

Mitigation measures, including stay-at-home orders and public mask wearing, together with routine public health interventions such as case investigation with contact tracing and immediate self-quarantine after exposure, are recommended to prevent and control the transmission of SARS-CoV-2, the virus that causes coronavirus disease 2019 (COVID-19) (1-3). On March 11, the first COVID-19 case in Delaware was reported to the Delaware Division of Public Health (DPH). The state responded to ongoing community transmission with investigation of all identified cases (commencing March 11), issuance of statewide stay-at-home orders (March 24-June 1), a statewide public mask mandate (from April 28), and contact tracing (starting May 12). The relationship among implementation of mitigation strategies, case investigations, and contact tracing and COVID-19 incidence and associated hospitalization and mortality was examined during March-June 2020. Incidence declined by 82%, hospitalization by 88%, and mortality by 100% from late April to June 2020, as the mask mandate and contact tracing were added to case investigations and the stay-at-home order. Among 9,762 laboratory-confirmed COVID-19 cases reported during March 11-June 25, 2020, two thirds (6,527; 67%) of patients were interviewed, and 5,823 (60%) reported completing isolation. Among 2,834 contacts reported, 882 (31%) were interviewed and among these contacts, 721 (82%) reported completing quarantine. Implementation of mitigation measures, including mandated mask use coupled with public health interventions, was followed by reductions in COVID-19 incidence and associated hospitalizations and mortality. The combination of state-mandated community mitigation efforts and routine public health interventions can reduce the occurrence of new COVID-19 cases, hospitalizations, and deaths.

The objective of this study was to describe the epidemiology of COVID-19 in Nigeria with a view of generating evidence to enhance planning and response strategies. A national surveillance dataset between 27 February and 6 June 2020 was retrospectively analysed, with confirmatory testing for COVID-19 done by real-time polymerase chain reaction (RT-PCR). The primary outcomes were cumulative incidence (CI) and case fatality (CF). A total of 40 926 persons (67% of total 60 839) had complete records of RT-PCR test across 35 states and the Federal Capital Territory, 12 289 (30.0%) of whom were confirmed COVID-19 cases. Of those confirmed cases, 3467 (28.2%) had complete records of clinical outcome (alive or dead), 342 (9.9%) of which died. The overall CI and CF were 5.6 per 100 000 population and 2.8%, respectively. The highest proportion of COVID-19 cases and deaths were recorded in persons aged 31-40 years (25.5%) and 61-70 years (26.6%), respectively; and males accounted for a higher proportion of confirmed cases (65.8%) and deaths (79.0%). Sixty-six per cent of confirmed COVID-19 cases were asymptomatic at diagnosis. In conclusion, this paper has provided an insight into the early epidemiology of COVID-19 in Nigeria, which could be useful for contextualising public health planning.

Marburg virus (MARV) causes sporadic outbreaks of severe Marburg virus disease (MVD). Most MVD outbreaks originated in East Africa and field studies in East Africa, South Africa, Zambia, and Gabon identified the Egyptian rousette bat (ERB; Rousettus aegyptiacus) as a natural reservoir. However, the largest recorded MVD outbreak with the highest case-fatality ratio happened in 2005 in Angola, where direct spillover from bats was not shown. Here, collaborative studies by the Centers for Disease Control and Prevention, Njala University, University of California, Davis USAID-PREDICT, and the University of Makeni identify MARV circulating in ERBs in Sierra Leone. PCR, antibody and virus isolation data from 1755 bats of 42 species shows active MARV infection in approximately 2.5% of ERBs. Phylogenetic analysis identifies MARVs that are similar to the Angola strain. These results provide evidence of MARV circulation in West Africa and demonstrate the value of pathogen surveillance to identify previously undetected threats.

Prior to the 2014-2016 Ebola epidemic, Sierra Leone's Ministry of Health and Sanitation had no infection prevention and control programme. High rates of Ebola virus disease transmission in healthcare facilities underscored the need for infection prevention and control in the healthcare system. The Ministry of Health and Sanitation led an effort among international partners to rapidly stand up a national infection prevention and control programme to decrease Ebola transmission in healthcare facilities and strengthen healthcare safety and quality. Leadership and ownership by the Ministry of Health and Sanitation was the catalyst for development of the programme, including the presence of an infection prevention and control champion within the ministry. A national policy and guidelines were drafted and approved to outline organisation and standards for the programme. Infection prevention and control focal persons were identified and embedded at public hospitals to manage implementation. The Ministry of Health and Sanitation and international partners initiated training for new infection prevention and control focal persons and committees. Monitoring systems to track infection prevention and control implementation were also established. This is a novel example of rapid development of a national infection prevention and control programme under challenging conditions. The approach to rapidly develop a national infection prevention and control programme in Sierra Leone may provide useful lessons for other programmes in countries or contexts starting from a low baseline for infection prevention and control. © Author(s) (or their employer(s)) 2019.