Visceral leishmaniasis (VL) is the most severe form of leishmaniasis caused by protozoan parasites of the genus Leishmania. Hepatomegaly is one of the most frequent clinical manifestations of VL, whereas immunopathology of the symptom has not been well investigated. Using our chronic model of experimental VL, we examined the influence of Leishmania donovani infection on the liver by clinical, histological, and biochemical analyses. The infected mice showed increased liver weight 24 weeks post-infection. Although an increase in serum ALT and inflammatory cell accumulation were observed in the livers of infected mice, no apparent parenchymal necrosis or fibrosis was observed. Tissue water content analyses demonstrated that increased liver weight was predominantly due to an increase in water weight. Together with the finding of hepatic sinusoidal dilation, these results suggested that edema associated with sinusoidal dilation causes hepatomegaly in L. donovani infection. Immunostaining of platelets and erythrocytes showed no thrombus formation or damage to the sinusoidal endothelium in the liver of infected mice. Taken together, these results suggest that hepatomegaly during experimental VL is caused by non-obstructive sinusoidal dilation.
Japanese encephalitis virus (JEV) genotype IV (GIV) is one of the least common and most neglected genotypes worldwide, having been identified only on a few Indonesian islands until it was recently found to be the cause of outbreaks that occurred in several Australian states in early 2022. Given the limited availability of information, the vector range for JEV GIV remains unknown; thus, understanding this range could prove invaluable for future prevention efforts in new areas. Herein, we experimentally exposed four mosquito colonies originated from various countries with no previous reports of GIV to JEV GIV strain 19CxBa-83-Cv, which was isolated from
Free-ranging cats are invasive species threatening biodiversity worldwide. They may also impose an environmental risk to humans and livestock through the transmission of zoonotic diseases. We investigated antibody levels against Toxoplasma gondii in free-ranging cats and black rats (definitive and representative intermediate hosts) by ELISA and determined their relationships with landscape environmental factors on Tokunoshima Island, Japan, the Natural World Heritage site. We found a higher seroprevalence (>70%) in both cats and black rats in landscapes where the cattle barn density was high. This was consistent with higher density of rats revealed in our trapping survey. The spatial scale of landscape factors affecting infection was broader in cats (1 km buffer radius) than in black rats (100 m buffer radius). Both cats and rats showed an increasing trend in optical density (OD) values with increasing body weight and landscape cattle barn density, suggesting that the antibody concentration increases as the chance of exposure to T. gondii in the environment increases. Thus, management actions to stop humans from feeding cats and to control rat populations without using cats are both necessary to reduce the human health risk as well as to conserve endangered species on the island.
To investigate the current mosquito fauna on Sado Island, we conducted surveillance in the Oosado mountainous area and the Kuninaka plain area from July 30 to August 3, 2019. In total, 20 species belonging to nine genera were collected. Among these, nine species in six genera were newly recorded on Sado Island. We also determined partial nucleotide sequences of the cytochrome c oxidase subunit I (COI) gene for 87 individuals of the 20 species and assessed the genetic divergence of their populations on Sado Island and the degree of differentiation between the Sado Island populations and those from mainland Japan or the Ryukyu Archipelagos.
Introduction: Parasitic diseases and Tuberculosis were shown to be the risk factor for each other. Co-infection of visceral leishmaniasis and pulmonary tuberculosis are increasing public health problem now a days especially in developing countries. More than 81% of cases and deaths from TB are in developing countries and is aggravated by concurrency with parasitic diseases.
Objective: To find out the occurrence of Leishmaniasis amongst Tuberculosis (TB) patients of Kala-azar endemic areas admitted to Surya Kanto (SK) Hospital, Mymensingh.
Materials and Methods: This descriptive cross-sectional study was conducted at Infectious and Tropical Disease Department of Mymensingh Medical College Hospital, a tertiary referral hospital from January 2014 to Decmber 2016. A total 176 TB patients reported from Kala-azar endemic areas admitted were included. For confirmation of diagnosis all cases of TB were sent for Gene expert before that relevant tests like CBC (Complete Blood Count), X-ray chest, Mantoux test, Smear tests were done. After having confirmed all the TB cases were investigated for Kala-azar. Venous blood was collected for buffy coat and serum for ELISA. All 176 patients’ blood were tested with ICT(rK39) for VL. There after splenic aspiration were done with full aseptic preparation for only those who were ICT positive. Smears were prepared and viewed under microscope with 10x 100 magnification. After that all these cases were tested by ELISA.
Results: A total of 176 TB patients were selected in this study of which 120(68.1%) were male and male-female ratio was 2.1: 1, the mean age was 43.06 years. Among patients 87.49% were within 16 to 60 years of age that means within productive age of life are infected more with TB. In terms of education 79.10%(139) patients were below Secondary level, that revealed the illiterate and or less literate people were affected more by TB. Maximum patient’s family 132(74.99%) had monthly income up to 10,000.00 BDT (125 US$)i.e. the poorer people of the area. Out of 176 patients Smear positive TB cases were 170(97.41%) but By Gene Xpert all 176 patients were found positive. The blood sample of 176 patients were tested with ICT rK39 and 12(6.81%) patients were found positive for leishmaniasis who suffered from TB. In splenic smear test 12 patients smear were examined of which 11(91.66%) were positive but by ELISA all 12(100%) were found positive.
Conclusion: Visceral leishmaniasis and tuberculosis co-infection have drawn attention to the clinical aspect. In both diseases infection may remain dormant asymptomatic which may be related to immune suppression and may lead to active disease. This study has been able to find out leishmaniasis amongst tuberculosis patients from kala-azar endemic areas of Bangladesh.
Journal of Armed Forces Medical College Bangladesh Vol.12(2) 2016: 3-8
Phlebotomus argentipes is a predominant vector of Leishmania donovani, the protozoan parasite causing visceral leishmaniasis in the Indian subcontinent. In hosts bitten by P. argentipes, sand fly saliva elicits the production of specific anti-salivary protein antibodies. Here, we have utilised these antibodies as markers of human exposure to P. argentipes in a visceral leishmaniasis endemic area in Pabna district, Bangladesh. The use of whole salivary gland homogenate as an antigen to detect these antibodies has several limitations, therefore it is being superseded by the use of specific recombinant salivary proteins. We have identified three major P. argentipes salivary antigenic proteins recognised by sera of bitten humans, expressed them in a recombinant form (rPagSP04, rPagSP05 and rPagSP06) and tested their applicability in ELISA and immunoblot. One of them, PpSP32-like protein rPagSP06, was identified as the most promising antigen, showing highest resemblance and correlation with the IgG response to P. argentipes salivary gland homogenate. Furthermore, we have validated the applicability of rPagSP06 in a large cohort of 585 individuals and obtained a high correlation coefficient for anti-rPagSP06 and anti-P. argentipes saliva IgG responses. The anti-rPagSP06 and anti-P. argentipes salivary gland homogenate IgG responses followed a similar right-skewed distribution. This is the first report of screening human sera for anti-P. argentipes saliva antibodies using recombinant salivary protein. The rPagSP06 was proven to be a valid antigen for screening human sera for exposure to P. argentipes bites in a visceral leishmaniasis endemic area.
