IMPORTANCE: Extensively drug-resistant Campylobacter jejuni infections cannot be treated with any commonly recommended antibiotics and pose an increasing public health threat. OBJECTIVES: To investigate cases of extensively drug-resistant C jejuni associated with pet store puppies and describe the epidemiologic and laboratory characteristics of these infections. DESIGN, SETTING, AND PARTICIPANTS: In August 2017, health officials identified, via survey, patients with C jejuni infections who reported contact with puppies sold by pet stores. In conjunction with state and federal partners, the Centers for Disease Control and Prevention investigated cases of culture-confirmed C jejuni infections in US patients with an epidemiologic or molecular association with pet store puppies between January 1, 2016, and February 29, 2020. Available records from cases occurring before 2016 with genetically related isolates were also obtained. MAIN OUTCOMES AND MEASURES: Patients were interviewed about demographic characteristics, health outcomes, and dog exposure during the 7 days before illness onset. Core genome multilocus sequence typing was used to assess isolate relatedness, and genomes were screened for resistance determinants to predict antibiotic resistance. Isolates resistant to fluoroquinolones, macrolides, and 3 or more additional antibiotic classes were considered to be extensively drug resistant. Cases before 2016 were identified by screening all sequenced isolates submitted for surveillance using core genome multilocus sequence typing. RESULTS: A total of 168 patients (median [interquartile range] age, 37 [19.5-51.0] years; 105 of 163 female [64%]) with an epidemiologic or molecular association with pet store puppies were studied. A total of 137 cases occurred from January 1, 2016, to February 29, 2020, with 31 additional cases dating back to 2011. Overall, 117 of 121 patients (97%) reported contact with a dog in the week before symptom onset, of whom 69 of 78 (88%) with additional information reported contact with a pet store puppy; 168 isolates (88%) were extensively drug resistant. Traceback investigation did not implicate any particular breeder, transporter, distributer, store, or chain. CONCLUSIONS AND RELEVANCE: Strains of extensively drug-resistant C jejuni have been circulating since at least 2011 and are associated with illness among pet store customers, employees, and others who come into contact with pet store puppies. The results of this study suggest that practitioners should ask about puppy exposure when treating patients with Campylobacter infection, especially when they do not improve with routine antibiotics, and that the commercial dog industry should take action to help prevent the spread of extensively drug-resistant C jejuni from pet store puppies to people.

Campylobacter jejuni is a leading cause of enteric bacterial illness in the United States. Traditional molecular subtyping methods, such as pulsed-field gel electrophoresis (PFGE) and 7-gene multilocus sequencing typing (MLST), provided limited resolution to adequately identify C. jejuni outbreaks and separate out sporadic isolates during outbreak investigations. Whole genome sequencing (WGS) has emerged as a powerful tool for C. jejuni outbreak detection. In this investigation, 45 human and 11 puppy isolates obtained during a 2016-2018 outbreak linked to pet store puppies were sequenced. Core genome multilocus sequence typing (cgMLST) and high-quality single nucleotide polymorphism (hqSNP) analysis of the sequence data separated the isolates into the same two clades containing minor within clade differences; however, cgMLST analysis does not require selection of an appropriate reference genome making this method preferable to hqSNP analysis for Campylobacter surveillance and cluster detection. The isolates were classified as ST2109-a rarely seen MLST sequence type. PFGE was performed on 38 human and 10 puppy isolates; PFGE patterns did not reliably predict clustering by cgMLST analysis. Genetic detection of antimicrobial resistance determinants predicted that all outbreak-associated isolates would be resistant to six drug classes. Traditional antimicrobial susceptibility testing (AST) confirmed a high correlation between genotypic and phenotypic antimicrobial resistance determinations. WGS analysis linked C. jejuni isolates in humans and pet store puppies even when canine exposure information was unknown, aiding the epidemiological investigation during this outbreak. WGS data were also used to quickly identify the highly drug-resistant profile of these outbreak-associated C. jejuni isolates.

During September 5–6, 2018, a total of 52 patients in Harare, Zimbabwe, were hospitalized with suspected cholera, an acute bacterial infection characterized by watery diarrhea. Rapid diagnostic testing was positive for Vibrio cholerae O1, and on September 6, Zimbabwe’s Ministry of Health and Child Care (MOHCC) declared an outbreak of cholera. From September 4, 2018, (date of the first reported cases) through March 12, 2019, a total of 10,730 cases and 69 (0.64%) deaths were reported nationally from nine of Zimbabwe’s 10 provinces (Figure). Most cases (94%) were reported from Harare Province, the country’s largest province, with a population of approximately 2 million.

On October 16, 2017, the Harare City Health Department (HCHD) in Zimbabwe identified a suspected typhoid fever (typhoid) case in a resident of Harare’s Mbare suburb. Typhoid is a potentially fatal illness caused by Salmonella enterica serovar Typhi (Typhi). HCHD initiated an investigation and identified a cluster of 17 suspected typhoid cases, defined as the occurrence of fever and at least one of the following symptoms: headache, malaise, abdominal discomfort, vomiting, diarrhea, cough, or constipation. A confirmed case had Typhi isolated from blood, stool, or rectal swab culture (1). | | As of February 24, 2018 (the most recent publicly available data), 3,187 suspected and 191 confirmed cases were identified (Figure), with no reported deaths among confirmed cases. Among suspected cases, 1,696 (53%) patients were male, and median age was 17 years (range = 1 month–90 years). In addition to clusters in Mbare, clusters were detected in Harare’s western suburbs, including Kuwadzana, where high rates of ciprofloxacin-resistant Typhi were identified.

In February 2018, a typhoid fever outbreak caused by Salmonella enterica serotype Typhi (Typhi), resistant to chloramphenicol, ampicillin, trimethoprim-sulfamethoxazole, fluoroquinolones, and third-generation cephalosporins, was reported in Pakistan. During November 2016-September 2017, 339 cases of this extensively drug-resistant (XDR) Typhi strain were reported in Pakistan, mostly in Karachi and Hyderabad; one travel-associated case was also reported from the United Kingdom (1). More cases have been detected in Karachi and Hyderabad as surveillance efforts have been strengthened, with recent reports increasing the number of cases to 5,372 (2). In the United States, in response to the reports from Pakistan, enhanced surveillance identified 29 patients with typhoid fever who had traveled to or from Pakistan during 2016-2018, including five with XDR Typhi. Travelers to areas with endemic disease, such as South Asia, should be vaccinated against typhoid fever before traveling and follow safe food and water practices. Clinicians should be aware that most typhoid fever infections in the United States are fluoroquinolone nonsusceptible and that the XDR Typhi outbreak strain associated with travel to Pakistan is only susceptible to azithromycin and carbapenems.

Campylobacter causes an estimated 1.3 million diarrheal illnesses in the United States annually (1). In August 2017, the Florida Department of Health notified CDC of six Campylobacter jejuni infections linked to company A, a national pet store chain based in Ohio. CDC examined whole-genome sequencing (WGS) data and identified six isolates from company A puppies in Florida that were highly related to an isolate from a company A customer in Ohio. This information prompted a multistate investigation by local and state health and agriculture departments and CDC to identify the outbreak source and prevent additional illness. Health officials from six states visited pet stores to collect puppy fecal samples, antibiotic records, and traceback information. Nationally, 118 persons, including 29 pet store employees, in 18 states were identified with illness onset during January 5, 2016-February 4, 2018. In total, six pet store companies were linked to the outbreak. Outbreak isolates were resistant by antibiotic susceptibility testing to all antibiotics commonly used to treat Campylobacter infections, including macrolides and quinolones. Store record reviews revealed that among 149 investigated puppies, 142 (95%) received one or more courses of antibiotics, raising concern that antibiotic use might have led to development of resistance. Public health authorities issued infection prevention recommendations to affected pet stores and recommendations for testing puppies to veterinarians. This outbreak demonstrates that puppies can be a source of multidrug-resistant Campylobacter infections in humans, warranting a closer look at antimicrobial use in the commercial dog industry.

On January 16, 2018, the Zimbabwe Ministry of Health and Child Care (MoHCC) was notified of five adults with watery diarrhea and severe dehydration who were admitted to Chegutu District Hospital, Mashonaland West Province. Three of the five patients died within hours of admission. Vibrio cholerae O1 serotype Ogawa was isolated from the stool sample of one decedent, prompting an investigation. During 2008–2009, Zimbabwe experienced one of the largest and deadliest cholera outbreaks in recent history (98,585 cases and 4,287 [4.3%] deaths), during which Chegutu reported a case fatality rate (CFR) >5% (1,2). During 2012–2016, Zimbabwe reported 93 cholera cases and two deaths nationwide, but the increasing population density and aging water and sanitation infrastructure in Chegutu raised concern about the possibility of another widespread outbreak.

In October 2016, the Harare City Health Department (HCHD) surveillance system recorded the beginning of an upward trend in typhoid cases. On December 27, 2016, after the typhoid fever–associated death of a student, the Ministry of Health and Child Care (MOHCC) in Zimbabwe declared an outbreak of typhoid fever. HCHD defined a suspected case in a resident of Harare City as an illness that began on or after October 6, 2016, with fever ≥100.4°F (38°C), body pains, headache, and abdominal pain. Patients with confirmed cases had blood or stool specimens positive for Salmonella Typhi. | | HCHD reported 860 cases with illness onset from October 6, 2016, through March 8, 2017, including 780 suspected cases, 80 confirmed cases, and four deaths (case fatality rate = 0.5%) (Figure). A spike in suspected cases on January 1 followed widespread media reports of the death of the student, but none of these cases were confirmed by lab testing. A total of 665 (77%) cases occurred in the high-density suburbs of Budiriro, Glen View, and Mbare; 24 (3%) patients were from outside Harare. Patients ranged in age from 1 month to 78 years (median age = 18 years); 48% were female.

RABORAL V-RG(R) is an oral rabies vaccine bait that contains an attenuated ("modified-live") recombinant vaccinia virus vector vaccine expressing the rabies virus glycoprotein gene (V-RG). Approximately 250 million doses have been distributed globally since 1987 without any reports of adverse reactions in wildlife or domestic animals since the first licensed recombinant oral rabies vaccine (ORV) was released into the environment to immunize wildlife populations against rabies. V-RG is genetically stable, is not detected in the oral cavity beyond 48 h after ingestion, is not shed by vaccinates into the environment, and has been tested for thermostability under a range of laboratory and field conditions. Safety of V-RG has been evaluated in over 50 vertebrate species, including non-human primates, with no adverse effects observed regardless of route or dose. Immunogenicity and efficacy have been demonstrated under laboratory and field conditions in multiple target species (including fox, raccoon, coyote, skunk, raccoon dog, and jackal). The liquid vaccine is packaged inside edible baits (i.e., RABORAL V-RG, the vaccine-bait product) which are distributed into wildlife habitats for consumption by target species. Field application of RABORAL V-RG has contributed to the elimination of wildlife rabies from three European countries (Belgium, France and Luxembourg) and of the dog/coyote rabies virus variant from the United States of America (USA). An oral rabies vaccination program in west-central Texas has essentially eliminated the gray fox rabies virus variant from Texas with the last case reported in a cow during 2009. A long-term ORV barrier program in the USA using RABORAL V-RG is preventing substantial geographic expansion of the raccoon rabies virus variant. RABORAL V-RG has also been used to control wildlife rabies in Israel for more than a decade. This paper: (1) reviews the development and historical use of RABORAL V-RG; (2) highlights wildlife rabies control programs using the vaccine in multiple species and countries; and (3) discusses current and future challenges faced by programs seeking to control or eliminate wildlife rabies.

BACKGROUND: Sustained genital tract inflammation caused by sexually transmitted infections (STIs) is known to increase risk of vaginal human immunodeficiency virus (HIV) infections but, to our knowledge, there are no nonhuman primate studies that have evaluated its link to rectal HIV acquisition. METHODS: Rhesus macaques inoculated with Chlamydia trachomatis (CT) (serovars LGV-L2 and CT-E; n = 7) or saline (n = 7) received up to 20 rectal challenges twice a week of simian/HIV immunodeficiency virus (SHIVSF162p3). SHIV viremia was determined by real-time PCR and Chlamydia infection by APTIMA Combo 2 testing. The rectal cytokine-chemokine levels were evaluated by multiplex bead assays. RESULTS: Rectal Chlamydia infection was maintained throughout the study. We did not observe significant differences (P = 1.0) in frequency of SHIV acquisition between the STI and control arms. It took fewer SHIV challenges to infect the STI animals although the difference was not significant (P = 0.59). There were no significant differences in peak plasma viremia between STI and control arms (P = 0.63). The association of plasma viremia with rectal shedding was significantly different by arm (P = 0.038). CONCLUSIONS: In the first such study in a macaque model, we did not observe an increased risk of SHIV acquisition due to rectal Chlamydia coinfection. This macaque model can be further developed and expanded to better investigate the impact of different rectal STIs on HIV acquisition.

BACKGROUND: Chlamydia trachomatis (CT) and Trichomonas vaginalis (TV), two prevalent sexual transmitted infections, are known to increase HIV risk in women and could potentially diminish pre-exposure prophylaxis (PrEP) efficacy, particularly for topical interventions that rely on local protection. We investigated in macaques whether co-infection with CT/TV reduces protection by vaginal TFV gel. METHODS: Vaginal TFV gel dosing previously shown to provide 100% or 74% protection when applied either 30 minutes or 3 days before SHIV challenge was assessed in pigtailed macaques co-infected with CT/TV and challenged twice-weekly with SHIV162p3 for up to 10 weeks (2 menstrual cycles). Three groups of six macaques received either placebo or 1% TFV gel 30 minutes or 3 days before each SHIV challenge. We additionally assessed TFV and TFV-diphosphate (TFV-DP) concentrations in plasma and vaginal tissues in CT/TV co-infected (n = 4) and uninfected (n = 4) macaques. RESULTS: CT/TV co-infections were maintained during the SHIV challenge period. All macaques that received placebo gel were SHIV-infected after a median of 7 challenges (1 menstrual cycle). In contrast, no infections were observed in macaques treated with TFV gel 30 minutes before SHIV challenge (p < 0.001). Efficacy was reduced to 60% when TFV gel was applied 3 days before SHIV challenge (p = 0.07). Plasma TFV and TFV-DP concentrations in tissues and vaginal lymphocytes were significantly higher in CT/TV co-infected compared to CT/TV uninfected macaques. CONCLUSIONS: Our findings in this model suggest that CT/TV co-infection may have little or no impact on the efficacy of highly effective topical TFV modalities and highlight a significant modulation of TFV pharmacokinetics.

BACKGROUND: Pre-Exposure Prophylaxis (PrEP) for HIV prevention is a novel biomedical prevention method. We have previously modeled PrEP during rectal SHIV exposures in macaques and identified that SHIV-specific T cell responses were induced in the presence of antiretroviral drugs, an observation previously termed T cell chemo-vaccination. This report expands those initial findings by examining a larger group of macaques that were given oral or topical PrEP during repeated vaginal virus exposure. METHODS: Thirty-six female pigtail macaques received up to 20 repeat low-dose vaginal inoculations with wild type (WT) SHIVSF162P3 (n=24) or a clonal derivative with the tenofovir K65R drug resistant mutation (n=12). PrEP consisted of oral Truvada (n=6, WT), tenofovir vaginal gel (n=6, K65R), or tenofovir intra-vaginal ring (n=6, WT). The remaining animals were PrEP-inexperienced controls (n=12, WT; n=6, K65R). SHIV-specific T cells were identified and characterized using IFNgamma ELISPOT and multi-parameter flow cytometry. RESULTS: Of nine animals that were on PrEP and remained uninfected during WT SHIV vaginal challenges, eight (88.9%) developed virus-specific T cell responses. T cells were in CD4 and CD8 compartments, reached up to 4,900 IFNgamma producing cells per million PBMCs, and primarily pol directed. In contrast, the replication impaired K65R virus did not induce detectable T cell responses, likely reflecting the need for adequate replication. CONCLUSION: Virus-specific T cell responses occur frequently in oral or topical PrEP-protected pigtail macaques after vaginal exposure to WT SHIV virus. The contribution of such immune responses to protection from infection during and following PrEP warrants further investigation.

T cell dysfunction is well documented during chronic viral infections but little is known about functional abnormalities in humoral immunity. Here we report that mice persistently infected with lymphocytic choriomeningitis virus (LCMV) exhibit a severe defect in Fcgamma-receptor (FcgammaR)-mediated antibody effector functions. Using transgenic mice expressing human CD20, we found that chronic LCMV infection impaired the depletion of B cells with rituximab, an anti-CD20 antibody widely used for the treatment of B cell lymphomas. In addition, FcgammaR-dependent activation of dendritic cells by agonistic anti-CD40 antibody was compromised in chronically infected mice. These defects were due to viral antigen-antibody complexes and not the chronic infection per se, because FcgammaR-mediated effector functions were normal in persistently infected mice that lacked LCMV-specific antibodies. Our findings have implications for the therapeutic use of antibodies and suggest that high levels of pre-existing immune complexes could limit the effectiveness of antibody therapy in humans.

FTY720 has been shown to reduce inflammatory cytokines and immune cells in the genital mucosa of macaques. This pilot study examined the ability of FTY720 to inhibit HIV acquisition. Systemic treatment with FTY720 failed to prevent or delay vaginal SHIV transmission.

BACKGROUND AND METHODS: Cell isolation from macaque tissues involves laborious enzymatic digestion. The Medimachine provides a simpler, quicker nonenzymatic method, yielding 1.5-5 million cells/g of vaginal or rectal tissue from pigtailed macaques. RESULTS AND CONCLUSIONS: Flow cytometry analysis of the two methods revealed similar levels of cell viability and most major cell lineage and activation markers.

Long-lived plasma cells that reside in the bone marrow constitutively produce antibody in the absence of antigen and are the cellular basis of durable humoral immunity. The generation of these long-lived plasma cells depends upon a series of highly orchestrated interactions between antigen-specific CD4 T cells and B cells and the formation of germinal centers (GCs). In this study, we have examined the role of the cytokine interleukin-21 (IL-21) in regulating humoral immunity during acute viral infections. Using IL-21 receptor-deficient (IL-21R(-/-)) mice, we found that virus-specific CD4 T cells were generated after infection with lymphocytic choriomeningitis virus (LCMV) and that these CD4 T cells differentiated into T follicular helper (TFH)-like cells in the absence of IL-21 signaling. There was also no defect in the formation of GCs, although after day 15 these GCs disappeared faster in IL-21R(-/-) mice than in wild-type mice. Isotype switching and the initial LCMV-specific IgG response were normal in IL-21R(-/-) mice. However, these mice exhibited a profound defect in generating long-lived plasma cells and in sustaining antibody levels over time. Similar results were seen after infection of IL-21R(-/-) mice with vesicular stomatitis virus and influenza virus. Using chimeric mice containing wild-type or IL-21R(-/-) CD4 T cells and B cells, we showed that both B and CD4 T cells need IL-21 signaling for generating long-term humoral immunity. Taken together, our results highlight the importance of IL-21 in humoral immunity to viruses.

Maraviroc (MVC) is a potent CCR5 co-receptor antagonist that is in clinical testing for daily oral pre-exposure prophylaxis (PrEP) for HIV prevention. We used a macaque model consisting of weekly SHIV162p3 exposures to evaluate the efficacy of oral MVC in preventing rectal SHIV transmission. MVC dosing was informed by the pharmacokinetic profile seen in blood and rectal tissues, and consisted of a human-equivalent dose given 24h before virus exposure followed by a booster post-exposure dose. In rectal secretions, MVC peaked at 24h (10,242 ng/ml) with concentrations at 48h that were about 40 times those required to block SHIV infection of PBMCs in vitro. Median MVC concentrations in rectal tissues at 24h (1,404 ng/g) were 30 and 10 times those achieved in vaginal or lymphoid tissues, respectively. MVC significantly reduced MIP-1beta-induced CCR5 internalization in rectal mononuclear cells, an indication of efficient binding to CCR5 in rectal lymphocytes. The half-life of CCR5-bound MVC in PBMCs was 2.6 days. Despite this favorable profile, 5/6 treated macaques were infected during 5 rectal SHIV exposures as were 3/4 controls. MVC treatment was associated with a significant increase in the percentage of CD3+/CCR5+ cells in blood. We show that high and durable MVC concentrations in rectal tissues are not sufficient to prevent SHIV infection in macaques. The increases in CD3+/CCR5+ cells seen during MVC treatment point to unique immunological effects of CCR5 inhibition by MVC. The implications of these immunological effects on PrEP with MVC require further evaluation.