Epidemiology of Plasmodium malariae infections in Venezuela
[Global Theme Issue on Poverty and Human Development]
Acta Cient Estud 2007; 5(4) : 186-188
Plasmodium malariae occurs in various tropical regions throughout the world and causes low, yet significant, morbidity and mortality levels in humans. In present report we reviewed P.malariae infections epidemiology in Venezuela, 1995-2002. For this period a total 275,791 malaria cases were reported, corresponding 449 to P.malariae (0.16%[0.1-0.4%]). P.malariae cases annual reported mean was 45+ 24.8/year (range 22-88). Although total malaria cases is increasing significantly (r2=.5238, p=.018), P.malariae annual rates and incidence is varying non-significantly (p>.05). From total cases, only 3 were fatal (0.7%), 2 male adults and 1 female elder. P.malariae deaths represented 0.9% of malaria fatalities.
P.malariae is commonly microscopically confounded with P.vivax and probably some cases really corresponded to P.malariae. Some studies have tried to determinate real P.malariae prevalence. In Asia, a total prevalence of P.malariae infection estimated by nested PCR reached 24.3% in individuals evaluated at northern, central and southern towns in Thailand along Myanmar border. In South America, i.e. Brazil, similar findings have been found using PCR, 10–12%, compared to 0-1.2% by thick blood smears. Oral CQ is choice treatment for uncomplicated P.malariae infections worldwide, although some reports suggest resistance in the Indonesian archipelago.
Although rare, P.malariae complications could be life-threatening (i.e. quartan malarial nephropathy). Species misidentification potential impact on malaria treatment and control is now under discussion in Venezuela, due to unpublished reports indicating rates high as 15-20% of P.malariae in southern country.