Sub-microscopic infections and long-term recrudescence of Plasmodium falciparum in Mozambican pregnant women.
BACKGROUND
Control of malaria in pregnancy remains a public health challenge. Improvements in its correct diagnosis and the adequacy of protocols to evaluate anti-malarial drug efficacy in pregnancy, are essential to achieve this goal.


METHODS
The presence of Plasmodium falciparum was assessed by real-time (RT) PCR in 284 blood samples from pregnant women with clinical complaints suggestive of malaria, attending the maternity clinic of a Mozambican rural hospital. Parasite recrudescences in 33 consecutive paired episodes during the same pregnancy were identified by msp1 and msp2 genotyping.


RESULTS
Prevalence of parasitaemia by microscopy was 5.3% (15/284) and 23.2% (66/284) by RT-PCR. Sensitivity of microscopy, compared to RT-PCR detection, was 22.7%. Risk of maternal anaemia was higher in PCR-positive women than in PCR-negative women (odds ratio [OR] = 1.92, 95% confidence interval [CI] 1.09-3.36). Genotyping confirmed that recrudescence after malaria treatment occurred in 7 (21%) out of 33 pregnant women with consecutive episodes during the same pregnancy (time range between recrudescent episodes: 14 to 187 days).


CONCLUSIONS
More accurate and sensitive diagnostic indicators of malaria infection in pregnancy are needed to improve malaria control. Longer follow-up periods than the standard in vivo drug efficacy protocol should be used to assess anti-malarial drug efficacy in pregnancy.
Mayor
Alfredo
A
Centre de Recerca en Salut Internacional de Barcelona, Hospital Clínic/Institut d'Investigacions Biomèdiques August Pi i Sunyer, Universitat de Barcelona, Rosselló 132, E-08036 Barcelona, Spain. agmayor@clinic.ub.es
Serra-Casas
Elisa
E
Bardají
Azucena
A
Sanz
Sergi
S
Puyol
Laura
L
Cisteró
Pau
P
Sigauque
Betuel
B
Mandomando
Inacio
I
Aponte
John J
JJ
Alonso
Pedro L
PL
Menéndez
Clara
C
D000328:Adult; D000818:Animals; D000953:Antigens, Protozoan / Q000235:genetics; D000962:Antimalarials / Q000627:therapeutic use; D002738:Chloroquine / Q000627:therapeutic use; D004338:Drug Combinations; D005260:Female; D005838:Genotype; D006801:Humans; D016778:Malaria, Falciparum / Q000188:drug therapy / Q000453:epidemiology / Q000469:parasitology*; D020066:Merozoite Surface Protein 1 / Q000235:genetics; D009073:Mozambique / Q000453:epidemiology; D018512:Parasitemia / Q000188:drug therapy / Q000453:epidemiology; D010963:Plasmodium falciparum / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification*; D016133:Polymerase Chain Reaction; D011247:Pregnancy; D015597:Pregnancy Complications, Parasitic / Q000188:drug therapy / Q000453:epidemiology / Q000469:parasitology*; D015995:Prevalence; D015800:Protozoan Proteins / Q000235:genetics; D011739:Pyrimethamine / Q000627:therapeutic use; D012008:Recurrence; D012680:Sensitivity and Specificity; D013413:Sulfadoxine / Q000627:therapeutic use
D000953:Antigens, Protozoan; D000962:Antimalarials; D004338:Drug Combinations; D020066:Merozoite Surface Protein 1; D015800:Protozoan Proteins; C065974:merozoite surface protein 2, Plasmodium; C001205:fanasil, pyrimethamine drug combination; D013413:Sulfadoxine; D002738:Chloroquine; D011739:Pyrimethamine