More than 20 species of pathogenic protozoan parasites of the genus
Data from 7112 patients from all 18 provinces (
Map of Iraq showing its 18 provinces. Permission to use the map granted by kind courtesy of MemNav. (Source: Figure 1
By contrast with the data for patients with CL from the broader Iraqi population, the later was classified based on demographic and environmental criteria. Total population, rural population, urban population, elevation, total annual rainfall and annual mean temperature for three consecutive years (2011–2013), were derived from Central Statistical Organization annual reports for each province [11].
Differences in occurrence were examined among sexes and age groups using chi-square tests. Spearman’s correlation coefficient was used for analyzing the effects of spatial, climate, and population factors on CL incidence. Both analyses were conducted using the Statistical Package for the Social Sciences for Windows (version 16, SPSS Inc).
A total of 7112 CL cases surveyed were reported from 2011–2013. During this time, there was a 44.6% overall decrease in the number of CL positive cases, from 2978 in 2011 to 1648 in 2013.
Sex and age of 7112 patients in Iraq with cutaneous leishmaniasis for the years 2011–20132011 2012 2013 Total n % n % n % number % Male 1741 58.5 1469 59.1 941 57.1 4151 58.4 Female 1237 41.5 1017 40.9 707 42.9 2961 41.6 <1 y 168 5.6 234 9.4 194 11.8 596 8.4 1–4 y 839 28.2 286 11.5 267 16.2 1392 19.6 5–14 y 905 30.4 607 24.4 367 22.3 1879 26.4 15–45 y 819 27.5 917 36.9 596 36.2 2332 32.8 >45 y 247 8.3 442 17.8 224 13.6 913 12.8 <1 y, male 109 3.7 108 4.3 107 6.5 324 4.6 <1 y, female 59 2.0 126 5.1 87 5.3 272 3.8 1–4 y, male 459 15.4 145 5.8 148 9.0 752 10.6 1–4 y, female 380 12.8 141 5.7 119 7.2 640 9.0 5–14 y, male 507 17.0 327 13.2 204 12.4 1038 14.6 5–14 y, female 398 13.4 280 11.3 163 9.9 841 11.8 15–45 y, male 481 16.2 578 23.3 356 21.6 1415 19.9 15–45 y, female 338 11.4 339 13.7 240 14.6 917 12.9 >45 y, male 145 4.9 311 12.5 126 7.6 582 8.2 >45 y, female 102 3.4 131 5.7 98 5.9 331 4.7
The distribution of cutaneous leishmaniasis among the Iraqi provinces for the years 2011–2013.Figure 2
The seasonal distribution of cutaneous leishmaniasis in Iraq for the years 2011–2013Figure 3
Cutaneous leishmaniasis, caused by
There are many factors that play critical roles in the incidence and distribution of CL in different parts of Iraq particularly in Diyala and Salahuddin, which showed the highest number of cases. These factors are the presence of animal reservoirs for ZCL, and the use of clay to build some of the houses in villages in these areas [15]. Clay maintains a sufficient level of moisture in the sand fly larval habitat so these houses facilitate sand fly breeding. The majority of CL cases occurred in provinces with a more rural population, these provinces have large agricultural areas that attract and harbor many species of insects, and the human population in these regions work mainly on farms where they are potentially more exposed to insect bites [18].
The majority of CL cases were noticed in provinces with low mean elevation. The level of elevation has an apparent effect on vector density. This finding is consistent with previous observations [19], which showed that most CL patients were from the dry and intermediate zones of the low-altitude areas. Landscapes with low elevations and with moderate or low annual rain falls and humidity are likely to be good for vegetation growth, which in turn allows maintenance and even expansion of the population of sand fly hosts. This scenario can potentially increase the infected sand fly numbers and thus the possibility of CL cases [20].
CL cases were more abundant in winter, with a peak in February. The incidence of infection then started to decline from April and reaches its lowest in July and August. This variation in seasonal peak could be the result of the existence of various dominant reservoir species in these areas particularly for ZCL, and the activity of the sand flies. The sand fly season in Iraq is from April through November and peaks in September–October. The incubation period of
This study has reported some initial data on the demographic and environmental correlates of CL. Such work is importance for making informed decisions regarding the assessment of possible management methods for the control of CL in Iraq.