Evaluation of the Surveillance and Epidemiological Aspects of Cutaneous Leishmaniasis in Babylon Province, Iraq

Leishmaniasis diseases constitute an important public health problem in both tropical and subtropical areas. The aim of this study is to evaluate the epidemiological situation of cutaneous leishmaniasis (CL) in Babylon province, Iraq. The current work included the recording of 142 new cases of CL infection in Babylon province for the period from November 2019 to February 2020. Male infection was represented by 87 cases (61.27%), while females composed 55 samples (38.73%), with a significant difference (p<0.05) between the two groups. The age group of 5-14 years was found to have the highest recorded CL cases (56; 39.44%), while the age group of less than one year had the lowest cases (1; 0.70%), with the differences being significant at p<0.05. Al-Gazali location was found to include the highest recorded CL cases (29; 20.42%), whereas Kish location had the lowest cases (1; 0.70%). The dry type of CL lesions was represented in 112 cases (78.9%), while the wet type was represented 30 cases (21.1%). The ulcero-crusted form of CL sores was more frequent (105; 73.7%), followed by the papulonodular form (30; 21.1%). According to the location of lesions, the upper limb lesions were more frequent (90; 63.16%), followed by the lower limb lesions (37; 26.32%). About 82 (57.9%) of the recorded CL cases were appearing as new cases, whereas 60 cases (42.1%) were recorded as a relapse after treatment. The study concludes that CL is highly distributed in Babylon province.


Introduction
Leishmaniasis diseases comprise important public health problems in both tropical and subtropical areas, mostly at all times [1]. Iraq is one of the areas that are endemic with cutaneous and visceral leishmaniasis [2,3]. Leishmaniasis is a common group of infections caused by common parasites called Leishmania spp.. which are protozoans transferred to humans through the bite of a common vector called sandfly which belongs to the Phlebotominae family of insects [4]. In general, the literature refers to the recording of three known forms of leishmaniasis based on clinical features, which are the visceral (VL), cutaneous (CL), and mucocutaneous (MCL). CL is recorded as the most common and widespread form [5].
Cutaneous leishmaniasis is the most common syndrome feature. It normally creates skin lesions on different locations of human body that are always exposed to sand fly biting, such as the face, neck, arms, legs, and perhaps abdomen. The number of lesions might reach two hundred on one body. Healing of ulcers often leaves permanent scars which, when present on the face, cause serious social problems [6].
CL has currently been endemic in 88 countries, covering most of the continents such as Asia, Africa, Europe, and America. About 350 million persons are considered being at risk for CL, with a worldwide prevalence of 12 million cases and annual incidence of 1.5 million cases. The causes of high prevalence of CL are exclusively related to climate change and shifts in anthropological environments [7]. Another study reported that the global incidence of CL ranges between 0.7 to 1.2 million annually [8]. The average annual incidence rate of CL was reported to have the range of 2.8 to 4.6 per 100,000 people in Jordan, Syria, KSA, Kuwait, and Turkey [8]. The records of CL prevalence revealed a range of 0.7 to 4.7% in Iran [9]. A study conducted in India recorded an incidence rate of CL of 2.5 per 1000 persons per year [10]. In Iraq, leishmaniasis is widespread. The incidence rate of CL was recorded as 5/100,000 individuals per year; it was reported that CL cases were peaked to 45.5 cases per 100,000 in 1992. Also, an outbreak was investigated as 300-400 cases were recorded in Diwaniyah province in 2008 [11]. In 2020, more than 200 cases were recorded in this study, which was conducted in Al-Madhatiya sub-distract (Al-Hashimiyah distract) , Babylon province, through a survey study in schools, health centers, and rural areas. In general, fourteen species of Leishmania are known to cause Leishmaniasis diseases to humans; these types may have similar or different clinical syndromes [12 ]. The causative agents of CL are confirmed in many countries, including those neighboring Iraq. In Iran, L. tropica was found to be the causative agent of anthroponotic cutaneous leishmaniasis (ACL), while L. major was found to be the causative agent of zoonotic cutaneous leishmaniasis (ZCL) [13]. In Saudi Arabia, L. major and L. tropica were found to be the etiological agents of cutaneous leishmaniasis [14,15]. In Kuwait, L. major is the causative agent of cutaneous leishmaniasis [5]. In Turkey, it is well-known that ACL is caused by L. tropica and zoonotic CL is caused by L. infantum and L. major [16]. In Jordan, CL was found to be caused by two types of parasites, namely L. major and L. tropica [17]. In Morocco, CL was found to be caused by three species, namely L. tropica, L. major, and L. infantum [18]. The aim of this study is to conduct an epidemiological survey of CL in Babylon province, Iraq.

Materials and Methods Study area
The present study was carried out in a focus of cutaneous leishmaniasis (according to health associations previous records) in Al-Hashimiyah distract, Babylon province (100km to the south of Baghdad) during the period from November 2019 to February 2020. Babylon province is located between 32° to 33.25° North latitude and 44° to 45° East longitude. The total area of Babylon is 5,119 km2 (1,976 sq mi). Population size according to a 2018 estimation is 2,065,042 people [19]. Babylon province is divided into four districts: Al-Mahawil District, Al-Musayab District, Al-Hashimiyah District and Al-Hilla District (Map1).

Cases collection and diagnosis
The incidence rate of CL was found to be 49/100,000 persons. CL cases were recorded at Al-Hashimiyah hospital in addition to 13 locations mentioned in Table-3. The period of collection was from November 2019 to February 2020. The data of CL cases in primary schools students were collected directly by authors. A total of 142 positive cases were recorded out of the 484 samples tested through the period of the study. The clinical diagnosis of the cases was performed by the physicians at Al-Hashimiyah Hospital.

Statistical Analysis
Statistical data were analyzed using the Statistical Package for Social Sciences (SPSS) version 25. Significant differences according to gender and age were calculated using Chi-square non parametric testes, under a probability level of 0.05. Descriptive statistics were calculated for the shape of CL, lesion size, lesion location, and number of lesions.

Results and discussion
A total of 142 CL cases were reported in Babylon province. The incidence rate of CL cases in Babylon according to the population size (2,065,042) was calculated to be 49/100,000 person. This rate is lower than other incidence rates that were recorded in other provinces and cities of Iraq; e.g. 45/10,000 in Salah Aldin (Alhaweja district) in 2009 [11] and 15/10,000 in Salah Aldin (Kirkuk city) in 2000 [19,20]. Male infection cases with CL were 87 (61.27%), while female infection cases were 55 (38.73%), with significant differences (p<0.001) ( Table-1). This result agrees with a study conducted in Iran in 2019, which found that the males constituted 94% of the infection cases. The authors attributed this difference to the facts that males in the studied community are more involved in outdoor activities and traditionally cover less parts of their skin as compared to females, which leads to higher exposure to sandflies [21].
The age group of 5-14 years was found to have the highest recorded CL cases (56; 39.44%), while the age group of less than one year had the lowest cases (1; 0.70%), with significant differences between the two groups (Table-2). The results of this study are in agreement with those of previous studies conducted in Iraq. For example, an earlier study showed that the age range of 1-14 years recorded the highest incidence of CL. The authors attributed this result to the weakness of children's immune system as compared to that of the adults, or the exposure to low doses of the parasite transmitted by sandflies. Furthermore, the results of the present study agree with those of another study [22], which found that the overall incidence of CL is greater among people who are 5-14 years old. This age is the school and work age in Iraq for both genders, who are more likely to participate in outdoor activities and be exposed to sandfly-associated environmental conditions. Also, L. tropica infections were reported to result in the development of life-time immunity [23], which may contribute to lower incidence in the oldest age groups [24].  Al-Gazali location was found to have the highest recorded CL cases (29; 20.42%), while Kish location had the lowest recorded cases (1; 0.71%) ( Table-3). The dry type of CL lesions was found in 112 cases (78.9%), while the wet type was found in 30 cases (21.1%) ( Table-4). These results are concordant with classical knowledge about the disease, as dry and wet lesion types are attributed to L. tropica lesions [16].  The ulcero-crusted form of CL was found to be more frequent (105; 73.7%), followed by the papulonodular form (30; 21.1%), and lastly the impetigenous form (7; 5.2%) ( Table-5). These results are in agreement with those reported by previous studies [25,26]. The latter study found that the ulcerated form has the most common presentation. It should be noted that CL may also be present in other unusual forms, such as the papulonodular, psoriasiform, and impetiginous. Most of CL lesions were 10mm 2 in size (67; 47.37%), followed by >30mm2 size (52; 36.83%), and lastly the 20mm 2 size (22; 15.80%) ( Table-6). The results of this study are in agreement with those of a previous study, which reported that the size of CL lesion in early stages was 52.1 mm 2 , whereas that in the late CL was 346.8mm 2 [27]. Also, these results are consistent with the findings of the Health Organization (WHO) [28], which reported that the size of most of the lesions was lower than 40mm 2 . The location of lesions was more frequent in the upper limbs (90; 63.16%), followed by the lower limbs (37; 26.32%), while the face and neck had equal frequencies (7; 5.26) ( Table-7; Figures -2A,  2B, and 2C). These results provide support to those previously reported [29], which found that the lesions were more frequent in upper limps than the lower limps. The authors stated that people who prefer to sleep outdoors are more exposed to bites at their upper and lower limbs as well as faces at night when the insects become more active. In addition, the distribution of the lesion depends on the parts of the body that are more exposed to sand fly bite. In addition, the results of the current study are consistent with those of another work which attributed the high frequency of lesions in the upper parts of the body to the probability that these sites are more exposed to flies. If the lesion location is on the extremities of the body, the location can be protected against bites by the dress, but if it is on the face, it is difficult to cover and easily exposed for biting during the active periods of sandflies in the night, which is important for spreading the parasite [16].  About 82 (57.9%) of the recorded CL cases appeared as new cases, but 60 cases (42.1%) of were recorded as a relapse after treatment (Table-8). These results are similar to those reported by an earlier study [30], which found relapsing lesions after ten months, which required further treatment. The highest number of sores recorded was two sores in 45 cases (31.6%), while the lowest number of sores was four sores recorded in 7 cases (5.2%) ( Table-9). The results agree with those of other studies which discussed the long periods of exposure to repeated and consecutive bites of sandflies as well as the high population density of sandflies in this area [29,31]. In general, the presence and distribution of lesions depend on which parts of the body are exposed and the susceptibility of the host [11].

Conclusions
The study concludes that the distribution of CL in Babylon province is high compared with other records. This result is due to the abundance of the vector and the formation of a reservoir of the disease with suitable environmental conditions.