American Journal of Tropical Medicine and Hygiene最新文献

In this article, we report a male patient infected with HIV presenting with cryptococcal meningitis, pneumonia, and bloodstream infection, along with intestinal obstruction and gastrointestinal bleeding. Cerebrospinal fluid and bloodstream analyses revealed the presence of Cryptococcus neoformans complex. The isolated strain was sequenced and was found to belong to Cryptococcus neoformans var. grubii with a new sequence type (ST). The strain led to fatal multisystemic cryptococcosis in a short time, and the patient died due to hemorrhagic shock because of gastrointestinal bleeding despite emergency rescue efforts. There are few reports about cryptococcosis in HIV-infected patients caused by new ST isolates. We report a new Cryptococcus neoformans ST (ST702) isolate causing infection in an HIV-infected patient, which merits further study and clinical attention.

Despite their colonial experience with tropical medicine, Allied (United States, United Kingdom, Australia, and India) Armies in the Indo-Pacific region were surprised by the large number of Plasmodium vivax infections in their soldiers during the Second World War. Even after the institution of effective chemoprophylaxis with quinacrine, multiple cycles of clinical relapses often occurred when months of medication was discontinued. Nearly monthly symptomatic relapses (>10) were not unusual and resulted in important manpower losses after each campaign. Retrospective consideration suggests that small splenic size was associated with the risk of recurrent clinical episodes of vivax malaria. Potential non-mutually exclusive explanations for frequent relapses of vivax malaria in soldiers are reviewed. These include decreased retention of parasitized red blood cells by small spleens through greater filtration stringency preventing relapses from becoming clinically patent; small spleen size being a marker of lower innate and/or acquired immunity, modulating the risk of clinically patent recurrences; or small spleen size increasing the number of relapses through decreased removal of triggers of hypnozoite activation. Apparent splenic modulation of vivax malaria relapses suggests a complex interaction between the parasite and host that might be amenable to manipulation to facilitate malaria elimination.

Mosquitoes are important vectors that transmit viral, protozoan, and helminthic diseases across the world. Climate change and unplanned urbanization are accelerating the spread of these diseases. Controlling vector-borne diseases can be performed most effectively through vector control. Inadequate knowledge of vector bionomics is an impediment and can lead to inappropriate vector control efforts. However, the conventional methods of vector identification are based on morphological differences, demand a significant amount of time and specific skills, and are often misleading. An efficient and affordable solution is needed to quickly and accurately identify pooled samples from vast geographical territories. To ensure the correct identification of distorted or pooled samples in India, a set of definitive steps is required, including the construction of unique primers and the standardization of a one-step assay based on the second internal transcribed spacer gene of the ribosomal DNA. We have successfully developed and confirmed a highly efficient one-step multiplex reverse transcriptase polymerase chain reaction assay for the accurate identification of major mosquito vectors, especially in the cases of both the adult and larval forms of Anopheles sp., Aedes sp., and Culex sp. Hence, the specificity, universality, and uniqueness of these primers could serve as a critical tool for the rapid one-step and one-reaction identification of mosquitoes to control mosquito-borne disease outbreaks and public health emergencies.

Although fresh vegetables are a vital source of essential nutrients and dietary fiber, they can pose a significant health risk due to contamination by intestinal parasites (IPs). The consumption of contaminated vegetables can lead to intestinal parasitic infection, which is a major public health issue, particularly in tropical and subtropical regions, where sanitation, clean water, and agricultural practices are often inadequate. Northeast Thailand, with its warm, humid climate and predominant agricultural sector, exhibits a high prevalence of IPs in humans. This study aimed to determine the prevalence of intestinal parasitic contamination in vegetables in Khon Kaen, Thailand, because of its reported high prevalence of IPs. A total of 300 samples, including cilantro, celery, Thai basil, lettuce, cucumber, Chinese kale, white cabbage, Chinese cabbage, peppermint, and yard-long beans, were collected from 10 markets across five districts in the province. Each sample was washed with 1% normal saline, shaken for 15 minutes, and allowed to sediment. The sediment was then centrifuged and examined by parasitologists under a microscope. The overall prevalence of IPs was found to be 36.0%, with Blastocystis hominis (24.7%), Strongyloides stercoralis (13.0%), and Ascaris lumbricoides (8.7%) being the most common. Peppermint showed the highest prevalence rate at 70.0%, followed by celery and Thai basil at 53.3% each. These results suggest a necessity for key health policy interventions, including appropriate health education. Sanitary measures, such as washing vegetables before consumption and washing hands after harvesting vegetables, should be encouraged among farmers, sellers, and consumers.

During the 33rd Africa Cup of Nations (AFCON) football tournament in Cameroon, organizers and health authorities required a negative SARS-CoV-2 test result <48 hours before entry and provided free SARS-CoV-2 testing and vaccination at stadium and fan zone entrances. We describe the outcomes and implementation of mandatory SARS-CoV-2 testing at fan zones during AFCON. All consenting fan zones attendees were administered an electronic questionnaire capturing exposure factors, COVID-19-like symptoms, and COVID-19 vaccination status, before being tested for SARS-CoV-2 using an antigen rapid diagnostic test (Ag-RDT). Participants testing positive were sampled for confirmatory real-time SARS-CoV-2 polymerase chain reaction (PCR) and sequencing for variant surveillance. The case detection rate was estimated using PCR-confirmed cases, and the challenges were summarized from staff discussions and project/study documentation. In total, 4,820 fan zone attendees (median [interquartile range] age 30 [24-38], 27.7% females) were tested for SARS-CoV-2, including 1,228 (25.5%) fully vaccinated. Of 4,820 participants, 148 (3.1%) had a positive Ag-RDT result, of whom 67 consented to PCR testing and 19 of 64 (29.7%) were confirmed PCR-positive. The case detection rate was 40.1 (95% CI: 24.2-62.7) per 10,000 attendees. The Omicron variant (B.1.1.529) was found in all 11 samples successfully sequenced. The implementation of mandatory SARS-CoV-2 Ag-RDT at fan zone entrances was challenged by high attendance volume just prior to matches, lobbying of economic stakeholders, and inconsistent quality assurance when using test kits. Despite the challenges encountered, implementing mandatory SARS-CoV-2 Ag-RDT at fan zones, was a unique opportunity for SARS-CoV-2 case identification and genomic surveillance.

The early detection and management of infections is crucial to control epidemics. We evaluated the feasibility and utility of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antigen rapid diagnostic tests (Ag-RDTs) for the timely detection of and response to coronavirus disease 2019 in high-risk border communities in Uganda. Between May and September 2022, monthly cross-sectional surveys were conducted in 11 schools and two markets in two border districts. Only baseline and end-line testing were also performed in matched control communities. Antigen rapid diagnostic test results and demographic and clinical data were collected, and contacts of patients were traced and tested. All patients were advised to self-isolate, and compliance was assessed on day 5. We enrolled 10,406 participants out of 10,472 screened individuals. The participants had a 1.3% test positivity rate, with schools recording higher, but non-significant, positivity rates than markets (1.4% versus 0.9%; P = 0.149). We tracked 556 contacts, and 536 (96.4%) agreed to test. The test positivity rate was significantly higher among contacts than the index participants (8.8% versus 1.3%; P <0.001). Only 55 (29.7%) of the index participants self-isolated effectively. Settings that received monthly testing had lower end-line positivity rates than controls (0.3% versus 1.4%; P = 0.001). Repeated SARS-CoV-2 Ag-RDT testing is feasible and could reduce SARS-CoV-2 infections. However, the participation in testing may have been enhanced by the compensation provided. Also, isolation was limited, which may reduce the impact of the intervention when rolled out on a large scale. Innovative strategies to increase the isolation of patients could improve the utility of early testing for transmission reduction during epidemics.

Acute undifferentiated febrile illness (AUFI) is the main cause of medical attention in the tropics worldwide. Malaria, arboviral diseases, and leptospirosis are the most important etiologies. These are highly endemic in the Urabá antioqueño, Colombia, being the main causes of fever in several municipalities in this region. However, up-to-date data regarding the infecting species and serotypes are lacking. Thus, we characterized the etiology of AUFI, focusing on malaria, arboviruses, and leptospirosis in this region and the circulating infecting species. An active surveillance was conducted between January and April 2022, and July and October 2023 in two local hospitals in the Urabá antioqueño. Febrile patients were enrolled voluntarily. Malaria, arboviral diseases, and leptospirosis were screened through direct, serological, molecular, and rapid diagnostic methods. Amplicons obtained for dengue virus (DENV) and Leptospira spp. were analyzed through phylogenetic analysis. A total of 184 febrile patients were enrolled. A confirmed etiology was detected in 43.4% of patients from Apartadó and 61.2% from Turbo. Malaria was the most frequent cause in both municipalities, which was caused mainly by Plasmodium falciparum in Apartadó and Plasmodium vivax in Turbo. Dengue virus serotype 1 genotype V, DENV genotype Asian-American, and DENV genotype Cosmopolitan were identified, as well as pathogenic Leptospira species closely related to Leptospira santarosai and Leptospira noguchii. The present study confirms the importance of malaria, dengue fever, and leptospirosis in the Urabá antioqueño. Plasmodium falciparum and P. vivax were identified, as well as two DENV serotypes and three DENV genotypes and two different Leptospira species.

Deworming for pregnant women using a single dose of albendazole or mebendazole is recommended by the WHO in areas where the baseline prevalence of hookworm and/or trichuriasis is >20%. However, other helminths and protozoa infecting pregnant women are not affected by these drugs and dosages. To assess the prevalence and diversity of intestinal helminth and protozoan infections, we analyzed stool samples from pregnant women recently enrolled into a birth cohort, along a rural-urban gradient in northern coastal Ecuador from 2019 to 2022. Participants provided a stool sample in their third trimester (n = 444). Samples were concentrated by the Ritchie method and observed microscopically for the detection of cysts, eggs, and larvae. The overall prevalence of infection with one or more parasites was 69% (95% CI: 67-74%), ranging from 52% in urban participants to 76% in rural participants (percentile rank = 1.39, 95% CI: 1.07-1.87). This differential between urban and rural communities persisted when data were disaggregated into helminth and protozoan infections (prevalence = 19% and 46%, respectively, in urban participants compared with 42% and 58% among rural participants). The most prevalent helminth was Ascaris lumbricoides (27%), followed by Trichuris trichiura (13%) and hookworm (7.4%). Hymenolepis nana, Strongyloides stercoralis, and Enterobius vermicularis were also observed. Six protozoan pathogens were detected, including Entamoeba histolytica/dispar (23%), Giardia intestinalis (5%), and Balantidium coli, along with nine protozoa that are nonpathogenic or of debated pathogenicity. The high infection burden and diversity of intestinal parasites found in this study highlight a need to revise strategies for preventing and treating intestinal parasitic infections in pregnant women.

Mainstreaming neglected tropical diseases (NTDs) interventions in national health systems is one of the key strategies emphasized in the WHO Roadmap for NTDs. However, there is limited evidence on implementing the proposed mainstreaming approaches effectively. We used a participatory ranking methodology in Ethiopia, using consultative workshops with purposively selected stakeholders, including NTDs program leaders from the government and partners, primary health care (PHC) workers, and community leaders and volunteers. Our aim was to identify, rank, and contextualize mainstreaming challenges and strategies, which were then synthesized using the Primary Health Care Performance Initiative framework. Thirty-three stakeholders at the national, regional, district, PHC, and community levels participated in two consultative workshops conducted in the Adama and Shashemene towns in Ethiopia. The stakeholders identified 73 mainstreaming challenges related to service delivery (32 [43.8%]), inputs (22 [30.1%]), systems (18 [24.7%]), and outputs (1 [1.4%]). The top three most frequently cited and ranked challenges were poor data recording and reporting, poor drug management and logistics, and weak supportive supervision and monitoring. Among the 185 strategies identified to address these challenges, the three most frequently cited were establishing a strong, supportive supervision and monitoring system, continuous on-the-job training to build workforce competence, and performance-based motivation. Multifaceted NTDs campaign intervention mainstreaming challenges that are deep-rooted in the health system were identified. The suggested strategies to address them should be given due consideration not only to guide future mainstreaming efforts but also to facilitate health system strengthening.

Neurocysticercosis (NCC) is a common parasitic neuroinfectious disease caused by humans becoming intermediate hosts in the life cycle of the pig tapeworm, Taenia solium, after ingesting its eggs. This case series examines seven female patients with NCC who engaged in geophagy (soil consumption) and were evaluated at Centre Médical Baraka in Lubumbashi, Democratic Republic of the Congo, from January 2019 to December 2020. From a cohort of 176 patients with epilepsy evaluated during that period, 105 underwent brain computed tomography scans, and 36 were confirmed to have NCC. Among those with NCC, seven (19.4%) had a history of geophagy and were included in this case series. The majority of these patients had more than five brain lesions. Neuroimaging revealed colloidal lesions, third-stage lesions, and calcifications in six patients. All patients showed improvement after treatment with antiseizure medication alone or in combination with antiparasitic drugs. Geophagy, although not common, serves as a mode of contamination in which individuals ingest soil containing Taenia eggs, potentially leading to the development of NCC.