HIV immunosupression and malaria: Is there a correlation?

Immunological disturbances associated with malarial infection

Malaria is a reemerging disease in the countries where it was eradicated previously, whereas it is endemic in many countries including tropical countries. In India, malarial infection is on rise due to rapid urbanization and overcrowding in all major metropolitan cities. The incidence of morbidity and mortality due to malaria infection is increasing and could be attributed to drug resistance in strains of malarial parasite. Combining immune modulation strategies with anti-malarial drugs has a beneficial effect in an attempt to improve treatment for malaria. Along with clinical presentation and outcome of this parasitic infection, it is important to understand immunological disturbances associated with biological mechanisms underlying these actions in better understanding of pathogenesis of malarial infection. Immune and inflammatory responses in malarial infection are controlled and co-ordinated by various cytokines and chemokines. This review focuses on commonly seen immunological disturbances associated with malarial infection resulting in related humoral and cell mediated immune functions primarily with innate to subsequent adaptive immunity in tackling this parasitic infection.

[Imported malaria and HIV infection in Madrid. Clinical and epidemiological features]

INTRODUCTION

Few data are available in Spain data on human immunodeficiency virus (HIV) patients coinfected with malaria. This study has aimed to determine the epidemiological and clinical characteristics of imported malaria in patients coinfected with HIV.

PATIENTS AND METHODS

A case-series retrospective study was performed using the patient's medical records. The study population consisted on patients diagnosed with malaria attended in our center from january 1, 2002 to december 31, 2007.

RESULTS

A total of 484 episodes of malaria, 398 of which were included in this study, were identified. Co-infection with HIV was described in 32 cases. All of them occurred in individuals presumably with some degree of semi-immunity. In the coinfected group, there were 13 cases (40.6%) asymptomatic, whereas this event occurred in 99 cases of patients not coinfected (37.2%) (P=0.707). The greater presence of anemia in co-infected patients (62.5% vs 32.3% in non-coinfected [P=0.001]) stands out.

CONCLUSIONS

In present study, the clinical presentation forms were similar, regardless of the presence or absence of HIV infection. Although the study population does not reflect all possible scenarios of malaria and HIV coinfection, our results indicate the reality of patients attended in the Autonomous Community of Madrid.

An intra-host mathematical model on interaction between HIV and malaria

In this paper a mathematical model is proposed for the interaction of the immune system with HIV viruses and malaria parasites in an individual host. It consists of a system of three coupled ordinary differential equations, which represents the rate of change in the concentration of malaria parasites, HIV viruses and immunity effector within a host, respectively. The theoretical model gives insight into the biological balance between pathogen replication and the immune response to the pathogen: persistence versus elimination of the pathogen, which determines the outcome of infection. Dynamical analysis shows that the outcomes of the interactions between the immune system of the host with either malaria parasites or HIV viruses are dramatic such as malaria infection promoting proliferation of HIV virus, HIV infection increasing the risk from malaria and the immune system of the host failing to keep the diseases under control, etc. The results provide a new perspective for understanding of the complexity mechanisms of the co-infection (or dual infection) with malaria and HIV in a host.