RESUMEN
A cross sectional malariometric parasitic survey including 4000 Yemenis of various age/sex groups from 43 villages or harah in five selected districts representing Al-Hodeidah Governorate was done. Duplicate thin and thick blood smears were stained with Giemsa stain and examined. Out of 4000 examined slides, 646 were found to be malaria positive, 508 of them were detected through ACD, while 138 cases were detected by PCD. The overall parasite rate was 16.2%, a situation of prevalently mesoendemic condition. P. falciparum was the predominant species [96.7%], followed by P. vivax [1.7%] and the least prevalent was P. malariae [0.3%]. Yemen has been considered free of ovale malaria. The recorded indigenous case of P. ovale for the first time in Yemen should be taken into consideration for the existence of this particular Plasmodium species when surveying for malaria in future studies. The present study was the first document in Yemen to compare simultaneously the in vivo and in vitro response to chloroquine among 209 of P. falciparum field isolate patients that were satisfied all criteria of WHO for the implementation of the in vivo and in vitro tests and were obtained by PCD and ACD methods. Chloroquine resistance of local strain of P. falciparum was recorded in all studied districts [Zabid, Bajil, Azohrah, Azaidiah and Al- Hodeidah City]. RIII [high level of resistance] was recorded for the first time in Yemen and should be taken into consideration in the treatment of infected malaria patients