Conference 2021 Live Talk

 

Talk title

Concomitant infection of Leishmania Donovani and Plasmodium Berghei reduces disease severity in BALB/c mice

 

Authors and Affiliations

Rebeccah. M. Ayako1, 2, Joshua. M. Mutiso1, John. C. Macharia2, Lucy. Ochola2

1. Department of Zoological Sciences, Kenyatta University, Nairobi, Kenya
2. Department of Tropical and Infectious Diseases, Institute of Primate Research, Nairobi, Kenya

 

Abstract

Background

Malaria and visceral leishmaniasis coexist in the same geographical regions. However, dual co-infection with parasites causing these diseases and their impact on public health is poorly documented. Interactions between these parasites may play a role in disease outcome. The present study set out to evaluate the clinical, parasitological outcome and humoral immune response following Leishmania donovani and Plasmodium berghei co-infection in BALB/c mice.

Methods

Mice were divided into four groups; L. donovani- only, L. donovani- P. berghei, P. berghei- only and naïve. Body weight, L. donovani parasite load, P. berghei parasitaemia and total IgG responses were determined. Spleen, liver and brain tissues were obtained for histological analysis. Four mice from each group were used for monitoring the survival rate.

Results

Results indicated significant differences in body weight (P<0.0001), L. donovani parasite load (P< 0.0001), L. donovani IgG (P< 0.0001), P. berghei parasitaemia (P= 0.0345, 0.0222) and P. berghei IgG (P= 0.02, 0.002) in both single and dual infections respectively. There was no correlation between L. donovani parasite load and IgG responses in single or dual infections, while a positive relationship of P. berghei parasitaemia and IgG responses was observed in the dual infected group only. Histological analysis revealed the enlargement of red and white pulps and the formation of granulomas in the spleen and vascular degeneration in the liver which were more pronounced in single infected groups. Leukocyte sequestration and microhemorrhages were more defined in the P. berghei- group. Plasmodium berghei had the highest mortality rate compared to L. donovani- only and L. donovani- P. berghei infected mice groups.

Conclusions

We conclude that L. donovani- P. berghei co-infection reduces disease severity in terms of humoral responses and disease course in BALB/c mice and this may predictably lead to inaccurate disease diagnosis in clinical settings. Better control strategies for endemic regions need to be expanded to alleviate the high mortality and morbidity rates currently observed.