BACKGROUND: A better understanding of SARS-CoV-2 infection risk among Hispanic and Latino populations and in low-resource settings in the United States is needed to inform control efforts and strategies to improve health equity. Puerto Rico has a high poverty rate and other population characteristics associated with increased vulnerability to COVID-19, and there are limited data to date to determine community incidence. OBJECTIVE: This study describes the protocol and baseline seroprevalence of SARS-CoV-2 in a prospective community-based cohort study (COPA COVID-19 [COCOVID] study) to investigate SARS-CoV-2 infection incidence and morbidity in Ponce, Puerto Rico. METHODS: In June 2020, we implemented the COCOVID study within the Communities Organized to Prevent Arboviruses project platform among residents of 15 communities in Ponce, Puerto Rico, aged 1 year or older. Weekly, participants answered questionnaires on acute symptoms and preventive behaviors and provided anterior nasal swab samples for SARS-CoV-2 polymerase chain reaction testing; additional anterior nasal swabs were collected for expedited polymerase chain reaction testing from participants that reported 1 or more COVID-19-like symptoms. At enrollment and every 6 months during follow-up, participants answered more comprehensive questionnaires and provided venous blood samples for multiantigen SARS-CoV-2 immunoglobulin G antibody testing (an indicator of seroprevalence). Weekly follow-up activities concluded in April 2022 and 6-month follow-up visits concluded in August 2022. Primary study outcome measures include SARS-CoV-2 infection incidence and seroprevalence, relative risk of SARS-CoV-2 infection by participant characteristics, SARS-CoV-2 household attack rate, and COVID-19 illness characteristics and outcomes. In this study, we describe the characteristics of COCOVID participants overall and by SARS-CoV-2 seroprevalence status at baseline. RESULTS: We enrolled a total of 1030 participants from 388 households. Relative to the general populations of Ponce and Puerto Rico, our cohort overrepresented middle-income households, employed and middle-aged adults, and older children (P<.001). Almost all participants (1021/1025, 99.61%) identified as Latino/a, 17.07% (175/1025) had annual household incomes less than US $10,000, and 45.66% (463/1014) reported 1 or more chronic medical conditions. Baseline SARS-CoV-2 seroprevalence was low (16/1030, 1.55%) overall and increased significantly with later study enrollment time (P=.003). CONCLUSIONS: The COCOVID study will provide a valuable opportunity to better estimate the burden of SARS-CoV-2 and associated risk factors in a primarily Hispanic or Latino population, assess the limitations of surveillance, and inform mitigation measures in Puerto Rico and other similar populations. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR1-10.2196/53837.

Background: Infection with Zika virus (ZIKV) during pregnancy is known to cause birth defects and could also be linked to pregnancy loss. Case: A pregnant woman in Puerto Rico contracted ZIKV at 16 weeks gestation. ZIKV RNA persisted in serum from her initial test at 16 weeks through 24 weeks gestation, when fetal demise occurred, and was detected in placental tissue. Conclusion: Prolonged detection of ZIKV RNA in maternal serum was associated with ZIKV RNA detection in the placenta of a patient who experienced fetal demise. While detection of placenta ZIKV RNA does not establish that ZIKV conclusively caused the demise, these findings support emerging evidence that the placenta may serve as a reservoir for ZIKV, which may be associated with prolonged detection of ZIKV RNA in serum.

OBJECTIVE: The aim of this study was to describe individuals seeking care for injury at a major emergency department (ED) in southern Puerto Rico in the months after Hurricane Maria on September 20, 2017. METHODS: After informed consent, we used a modified version of the Natural Disaster Morbidity Surveillance Form to determine why patients were visiting the ED during October 16, 2017-March 28, 2018. We analyzed visits where injury was reported as the primary reason for visit and whether it was hurricane-related. RESULTS: Among 5 116 patients, 573 (11%) reported injury as the primary reason for a visit. Of these, 10% were hurricane-related visits. The most common types of injuries were abrasions, lacerations, and cuts (43% of all injury visits and 50% of hurricane-related visits). The most common mechanisms of injury were falls, slips, trips (268, 47%), and being hit by/or against an object (88, 15%). Most injury visits occurred during the first 3 months after the hurricane. CONCLUSIONS: Surveillance after Hurricane Maria identified injury as the reason for a visit for about 1 in 10 patients visiting the ED, providing evidence on the patterns of injuries in the months following a hurricane. Public health and emergency providers can use this information to anticipate health care needs after a disaster.

BACKGROUND: The burden of leptospirosis in Puerto Rico remains unclear due to underreporting. METHODS: A cross-sectional survey and rodent trapping was performed in a community within San Juan, Puerto Rico to determine the seroprevalence and risk factors for Leptospira infection. The microscopic agglutination test was used to detect anti-Leptospira antibodies as a marker of previous infection. We evaluated Leptospira carriage by qPCR among rodents trapped at the community site. RESULTS: Of 202 study participants, 55 (27.2%) had Leptospira agglutinating antibodies. Among the 55 seropositive individuals, antibodies were directed most frequently against serogroups Icterohaemorrhagiae (22.0%) and Autumnalis (10.6%). Of 18 captured rodents, 11 (61.1%) carried pathogenic Leptospira (L. borgpetersenii, 7 and L. interrogans, 2). Four participants showed their highest titer against an isolate obtained from a rodent (serogroup Ballum). Increasing household distance to the canal that runs through the community was associated with decreased risk of infection (OR = 0.934 per 10m increase, 95% CI: 0.952-0.992). CONCLUSION: There are high levels of Leptospira exposure in an urban setting in Puerto Rico, for which rodents may be an important reservoir for transmission. Our findings indicate that prevention should focus on mitigating risk posed by infrastructure deficiencies such as the canal.

Chikungunya and dengue are mosquito-borne, viral, acute febrile illnesses that can be difficult to distinguish clinically. Whereas dengue is endemic in many countries in the Caribbean and the Americas, the first locally acquired chikungunya case in the Western Hemisphere was reported from the Caribbean island of St. Martin in December 2013 and was soon followed by cases in many parts of the region. In January 2014, the Puerto Rico Department of Health (PRDH) and CDC initiated chikungunya surveillance by building on an existing passive dengue surveillance system. To assess the extent of chikungunya in Puerto Rico, the severity of illnesses, and the health care-seeking behaviors of residents, PRDH and CDC analyzed data from passive surveillance and investigations conducted around the households of laboratory-positive chikungunya patients. Passive surveillance indicated that the first locally acquired, laboratory-positive chikungunya case in Puerto Rico was in a patient with illness onset on May 5, 2014. By August 12, a total of 10,201 suspected chikungunya cases (282 per 100,000 residents) had been reported. Specimens from 2,910 suspected cases were tested, and 1,975 (68%) were positive for chikungunya virus (CHIKV) infection. Four deaths were reported. The household investigations found that, of 250 participants, 70 (28%) tested positive for current or recent CHIKV infection, including 59 (84%) who reported illness within the preceding 3 months. Of 25 laboratory-positive participants that sought medical care, five (20%) were diagnosed with chikungunya and two (8%) were reported to PRDH. These investigative efforts indicated that chikungunya cases were underrecognized and underreported, prompting PRDH to conduct information campaigns to increase knowledge of the disease among health care professionals and the public. PRDH and CDC recommended that health care providers manage suspected chikungunya cases as they do dengue because of the similarities in symptoms and increased risk for complications in dengue patients that are not appropriately managed. Residents of and travelers to the tropics can minimize their risk for both chikungunya and dengue by taking standard measures to avoid mosquito bites.

Co-infection with pathogens that cause acute febrile illness creates a diagnostic challenge as a result of overlapping clinical manifestations. Here, we describe four fatal cases of Leptospira species/dengue virus co-infection in Puerto Rico. Although all patients sought care early, antibiotic administration was delayed for most. Steroids were administered to all patients, in most cases before antibiotics. These cases show the need for clinicians evaluating patients in or recently returned from the tropics with acute febrile illness to consider both dengue and leptospirosis. Furthermore, they illustrate the need for nucleic acid- or antigen-based rapid diagnostic tests to enable timely patient diagnosis and management. In particular, antibiotic therapy should be initiated early for patients with suspected leptospirosis, and steroids should not be administered to patients with suspected dengue.