First Evidence of Aedes albopictus (Skuse) in Southern Chiapas, Mexico

Five (15.5%) of the 33 pregnant women had P. jiroveci DNA in their nasal swab samples versus none (0%) of the 28 nonpregnant controls (p=0.04 by 1-sided Fisher exact test). Immunologic parameters were not tested. The P. jiroveci–positive women were all multiparous with 1 (n=2), 2 (n=2), or 3 (n=1) previous pregnancies. These results suggest that pregnancy is a host factor that favors asymptomatic nasal carriage of P. jirovec. However, PCR detection of P. jiroveci DNA in the nares of pregnant women does not necessarily indicate either a mild active pulmonary infection or viable or transmissible organisms. In animal models, detection of P. carinii DNA in nasal and oral samples is a good indicator that Pneumocystis is in the lungs (8). These results also support the hypothesis that pregnant women who nasally carry P. jiroveci may play a role as contagious sources for susceptible persons, especially their immunologically naive newborn infants. This hypothesis warrants further study. Mother-to-infant transmission may explain the accumulating evidence that the primary infection is widely acquired very early in life (9). Recent animal model studies have documented the early acquisition of P. carinii (within 1 to 2 h after birth) in neonatal rats, likely transmitted by the dams (10). Evidence of mother-offspring transmission would be clinically relevant for infants born to HIVinfected mothers, who currently rely on empiric anti-Pneumocystis chemotherapy started at 1 month of age as their only prophylactic option.