Overcoming challenges in the diagnosis and treatment of parasitic infectious diseases in migrants

Chronic diarrhea and parasitic infections: Diagnostic challenges

BACKGROUND

Diarrhea is among the top ten global causes of death. Chronic diarrhea may have destructive impact on physical and mental health of patients and is also associated with high risk of mortality in children. Parasitic intestinal infections remain an important cause of chronic diarrhea especially in the developing part of the world.

OBJECTIVE

To study the parasitic causes of chronic diarrhea and highlight the challenges faced in the diagnosis of chronic diarrhea caused due to parasitic infections.

CONTENT

Due to non-specific symptoms, insensitive available diagnostic techniques, asymptomatic carriage and transmission, recurrent infections in endemic areas, pose a challenge for diagnosis of the parasitic infections and thus delay the treatment. Conventional techniques like microscopy, though cheaper are not very sensitive. Advanced techniques like molecular methods are more sensitive but expensive and are not readily available in resource limited settings. Newer cost-effective diagnostic techniques with higher sensitivity and specificity are required to detect the infectious agent and for appropriate management.

Spatial and Temporal Variability of Visceral Leishmaniasis in Colombia, 2007 to 2018

Visceral leishmaniasis (VL) is a neglected tropical disease associated with poverty and is endemic in 56 countries worldwide. Brazil, Venezuela, and Colombia are the most affected countries in South America. In Colombia, the National Public Health Surveillance System (SIVIGILA) consolidates epidemiological information and monitors all VL cases nationwide. However, to date, no studies have investigated the occurrence of VL in Colombia using metadata analysis. We studied the demographic data, the spatial and temporal distribution of VL cases, and the association with vector distribution of Leishmania species in Colombia from 2007 to 2018. We found 306 VL cases reported to SIVIGILA for this period, with a coverage of 25.5 cases/year, and a mortality of 2.28% (seven deaths). The highest number of confirmed cases (N = 52) occurred in 2007; the lowest (N = 9) occurred in 2012. The cases were reported mainly in children (< 7 years) affiliated with the subsidized health regimen. Regarding the geographic distribution, the cases were reported by 42 municipalities distributed in 10 departments. The occurrence of VL cases toward the northeast of Colombia, and the distribution of vectors, such as Lutzomyia longipalpis and Lu. evansi, may be changing the panorama of VL in the country. We conclude that VL, mainly in recent years, shows a temporal and spatial variability associated with the occurrence of cases in new settings. Our findings increase our understanding and knowledge of this disease, and suggest the need to monitor and prioritize areas with changes in geographic expansion to improve prevention and control actions in the country.

Challenges of Managing Skin Diseases in Refugees and Migrants

"Currently, an estimated 70.8 million individuals worldwide are forcibly displaced due to war, violence, and persecution. Barriers to providing dermatologic care include the large number of affected people, their movement within and across international borders, security issues, and limited access to dermatology expertise and formularies. Screening protocols for skin diseases and sexually transmitted infections differ worldwide, raising the need for shared guidelines to assess migrants' health. This article reviews the literature of skin and sexually transmitted infections in migrants and displaced persons, highlighting the impact of social determinants on skin health and challenges faced in providing care."

Recombinant micro-exon gene 3 (MEG-3) antigens from Schistosoma mansoni failed to induce protection against infection but show potential for serological diagnosis

Sequence databases on Schistosoma mansoni have revealed micro-exon gene (MEGs) families. Many of these genes are highly expressed in parasite life cycle stages associated with the mammalian host infection and appear to be involved in immune evasion by schistosomes. So, we believe that MEG-coding proteins would make potential candidates for vaccine development or diagnosis for schistosomiasis. Here, we study MEG-3.2 and MEG-3.4, members of the MEG-3 family. Recombinant (r) proteins were produced and formulated with Freund's adjuvant for vaccination of mice. Immunization with recombinant MEG-3.2 or MEG-3.4 formulation generated high levels of IgG1 antibodies. Additionally, vaccination also induced a mixed Th1/Th2/Th17-type of response, since IFN-γ, IL-5 and IL-17 cytokines were detected in the supernatant of spleen cell cultures; however it failed to induce reduction in parasitic worm burden. Finally, the recombinant proteins were evaluated in a serological assay using human samples. Schistosome-infected individuals showed higher levels of both IgG and IgM against rMEG-3.2 compared to non-infected individuals, while only IgM anti-rMEG-3.4 antibodies were elevated in infected patients. Therefore, between both studied molecules, MEG-3.2 protein is the antigen that shows potential to compose a serological diagnosis test for schistosomiasis.