Mohammad Reza Shirzadi

Surveillance and Laboratory Detection System of Crimean‐Congo Haemorrhagic Fever in Iran

Crimean-Congo haemorrhagic fever (CCHF) is a viral zoonotic disease with a high mortality rate in humans. The CCHF virus (CCHFV) is transmitted to humans through the bite of Ixodid ticks or by contact with blood or tissues of infected livestock. In addition to zoonotic transmission, CCHFV can be spread from person to person and is one of the rare haemorrhagic fever viruses able to cause nosocomial outbreaks in hospitals. Crimean-Congo haemorrhagic fever is a public health problem in many regions of the world such as Eastern Europe, Asia, the Middle East and Africa. In addition to clinical symptoms, the diagnosis of CCHF is based on the use of serological tests for the detection of immunoglobulin M and immunoglobulin G antibodies and on the use of molecular tools such as RT-PCR. From 1970 to 1978, serological and epidemiological studies were performed in humans and in livestock of Iran. After two decades and observations of CCHF in some provinces of Iran, a CCHF surveillance and detection system was established in 1999, leading to a dramatically decreased mortality rate from 20% (year 2000) to 2% (year 2007).

An observational study on the current distribution of visceral leishmaniasis in different geographical zones of Iran and implication to health policy

Visceral leishmaniasis is one of the most important parasitic diseases that is endemic in some parts of Iran. This study aimed to determine current distribution of visceral leishmaniasis in four distinct geographical zones of Iran. A cross-sectional study was conducted using direct agglutination test (DAT) on 9396 and 2559 serum samples collected from humans and domestic dogs, respectively during the period of 2007 through 2009. Altogether, 403 (4.3%) out of 9396 human serum samples collected from 4 distinct geographical locations showed anti-Leishmania antibodies with titers ≥ 1:3200. Physical examinations performed on 142 sero-positive cases with anti-Leishmania antibodies at titers of 1: 3200 to 1:102400 among whom fever (94.4%), paleness (67.6%) and hepato-splenomegaly (42.2%) were the predominant clinical signs and symptoms. The highest sero-prevalence rate (1.55%) was found in children ≤ 5 years old. Out of 2559 serum samples collected from domestic dogs, 212 (8.3%) were DAT positive (≥ 1:320). Leishmania infantum is the principal causative agent of the disease was isolated from both infected humans and dogs in Iran. Our findings indicate that Mediterranean visceral leishmaniasis with different distribution occurs in different geographical locations of Iran.

First report on isolation of Leishmania tropica from sandflies of a classical urban Cutaneous leishmaniasis focus in southern Iran

Shiraz district in south of Iran is a classical focus of Cutaneous leishmaniasis (CL) and previous research has consistently documented the etiologic agent to be Leishmania tropica and Leishmania major in urban and rural areas, respectively. However, none of the Phlebotomus sergenti, a known vector for L. tropica, of the region has been found infected. We report the first isolation of L. tropica from sandflies in urban community of southern part of Shiraz city. Parasite polymerase chain reaction (PCR) followed by restriction fragment length polymorphism (RFLP) and gene sequencing analyses indicate CL cases in this community were caused by either L. major or L. tropica. Sandflies of P. sergenti were infrequent, however, three out of 10 (30.0%) females captured in urban area were found infected with L. tropica. But, no human cases were found to be infected with L. tropica. Phlebotomus papatasi were found the most dominant and infected species where 41 out of 207 (20%) tested individuals harboring L. major in suburb area of the city. Patients have been lived in the suburb area of the city where people keep normally domestic animals in their houses which provide appropriate environment for completion of sandfly life cycle and expansion of CL disease in the region.

Geographic Information System-Based Analysis of the Spatial and Spatio-Temporal Distribution of Zoonotic Cutaneous Leishmaniasis in Golestan Province, North-East of Iran

Zoonotic cutaneous leishmaniasis (ZCL), a vector‐borne disease, poses serious psychological as well as social and economic burden to many rural areas of Iran. The main objectives of this study were to analyse yearly spatial distribution and the possible spatial and spatio‐temporal clusters of the disease to better understand spatio‐temporal epidemiological aspects of ZCL in rural areas of an endemic province, located in north‐east of Iran. Cross‐sectional survey was performed on 2983 recorded cases during the period of 2010–2012 at village level throughout the study area. Global clustering methods including the average nearest‐neighbour distance, Morans I, general G indices and Ripleys K‐function were applied to investigate the annual spatial distribution of the existing point patterns. Presence of spatial and spatio‐temporal clusters was investigated using the spatial and space–time scan statistics. For each year, semivariogram analysis and all global clustering methods indicated meaningful persistent spatial autocorrelation and highly clustered distribution of ZCL, respectively. Eight significant spatial clusters, mainly located in north and northeast of the province, and one space–time cluster, observed in northern part of the province and during the period of September 2010–November 2010, were detected. Comparison of the location of ZCL clusters with environmental conditions of the study area showed that 97.8% of cases in clusters were located at low altitudes below 725 m above sea level with predominantly arid and semi‐arid climates and poor socio‐economic conditions. The identified clusters highlight high‐risk areas requiring special plans and resources for more close monitoring and control of the disease.

Preliminary study of dengue virus infection in Iran.

Dengue fever is one of the most important arthropod-borne viral diseases of public health significance. It is endemic in most tropical and subtropical parts of the world, many of which are popular tourist destinations. The presence of dengue infection was examined in Iranian patients who were referred to the Arboviruses and Viral Haemorrhagic Fevers Laboratory of the Pasteur Institute of Iran and tested negative for Crimean-Congo Haemorrhagic Fever (CCHF) between 2000 and 2012. Serum samples from these patients were tested for the presence of specific IgG and IgM and viral nucleic acid in blood. Of the 300 sera tested, 15 (5%) were seropositive, and 3 (1%) were both serologically and PCR positive. Of the 15 seropositive cases, 8 (53.3%) had travelled to endemic areas including Malaysia (5, 62.5%), India (2, 25%) and Thailand (1, 12.5%). In contrast, 7 (46.7%) of the cases had not reported travelling abroad. Of these, six cases were from the Sistan and Baluchistan province in southeast Iran and neighbouring Pakistan. Travellers play a key role in the epidemiology of dengue infection in Iran and it is recommended that travellers to endemic areas take precautionary measures to avoid mosquito bites.

Seroepidemiological study of visceral leishmaniasis in Booyerahmad district, south-west Islamic Republic of Iran.

Visceral leishmaniasis (VL) is endemic in parts of Islamic Republic of Iran. A cross-sectional seroprevalence study was carried out in children in Booyerahmad district in the south-west of the country. Serum samples were taken from 1628 children up to 10 years old from different areas in Booyerahmad in 2005-06. AntiLeishmania antibody was detected in 50 out of 1628 children (3.1%) by direct agglutination test (antibody titre > or = 1:3200). There was no significant difference in seropositivity between the sexes (2.8% males and 3.3% females). The highest rate of infection (5.2%) was in the age group 10 years. Further studies are needed to explore the reservoirs and vectors of the disease in this region.

Ecological Niche Modeling of main reservoir hosts of zoonotic cutaneous leishmaniasis in Iran

Zoonotic cutaneous leishmaniasis (ZCL), caused by Leishmania major, is a common zoonotic vector-borne disease in Iran. Close contact with infected reservoir hosts increases the probability of transmission of Leishmania parasite infections to susceptible humans. Four gerbil species (Rodentia: Gerbillidae) serve as the main reservoir hosts for ZCL in different endemic foci of Iran. These species include Rhombomys opimus, Meriones libycus, Meriones hurrianae and Tatera indica; while notable infection has been reported in Nesokia indica as well. The purpose of this study is to model the distribution of these reservoirs to identify the risk areas of ZCL. A data bank was developed including all published data during the period of 1970-2015. Maximum entropy model was used to find the most appropriate ecological niches for each species. The areas under curve obtained were 0.961, 0.927, 0.922, 0.997 and 0.899, instead of 1, for training test in R. opimus, M. libycus, T. indica, M. hurrianae and N. indica, respectively. The environmental variable with the highest gain when used in isolation was slope for R. opimus and N. indica, annual mean temperature for M. libycus, and seasonal precipitation for T. indica and M. hurrianae. Summation of presence probabilities for three main species, i.e., R. opimus, M. libycus and T. indica revealed favorable ecological niches in wide areas of 16 provinces. This is the first study to predict the distribution of ZCL reservoir hosts in Iran. Climatology and topography variables had high contributions toward the prediction of potential distribution of the main reservoir species; therefore, as climate changes, the models should be updated periodically with novel data, and the results should be used in disease-monitoring programs.

Spatial and statistical analyses of the relations between vegetation cover and incidence of cutaneous leishmaniasis in an endemic province, northeast of Iran

Abstract Objective To investigate the relations between the vegetation cover and occurrence of cutaneous leishmaniasis (CL) in Golestan province during 2010–2012. Methods Data of monthly CL incidence and remote sensing normalized difference vegetation index (NDVI) of moderate resolution imaging spectroradiometer sensor were used in the study. Pearsons correlation analysis was conducted to examine the type and strength of relationships between the spatially averaged NDVI variables (i.e. minimum, maximum and mean NDVI values) and CL incidence in township level. Spearman rank correlation was carried out to explain associations between the monthly CL incidence and NDVI variables at 0, 1, 2, 3 and 4 months lagged periods. Locations of CL cases at village level were geocoded and compared with frequency of CL cases in each NDVI-derived vegetation categories. Results Pearsons analysis revealed significant associations between the NDVI variables and CL incidence at the township level (P Conclusions lack or low vegetation cover is a major determinant of CL frequencies in Golestan province. The decrease of the mean vegetation density in townships is accompanied by increase of CL occurrence and vice versa.

Seroprevalence of West Nile virus in Iran.

This study was undertaken to determine the seroprevalence of West Nile virus (WNV) in human and equine sera in Iran. Blood samples were tested from 300 human samples and 315 equine samples in five geographic zones of north and central parts of Iran between 2010 and 2012. All samples were tested for the immunoglobulin G (IgG) antibody to WNV by using an enzyme-linked immunosorbent assay (ELISA). Of all samples, 4 (1.3%) human and 9 (2.8%) equines were considered to be seropositive for WNV. These results suggest circulation and exposure of the human and equine populations to WNV in Iran.

Integrated visceral leishmaniasis surveillance system in primary care for children in Meshkin-Shahr district, north-western Islamic Republic of Iran

In 2001 a visceral leishmaniasis (VL) surveillance system was set up for children aged < or = 12 years in the primary health system in Meshkin-Shahr district of Ardebil province, north-western Islamic Republic of Iran. All cases with clinical signs and symptoms of VL and positive by the direct agglutination test were referred for physical examination and treatment. The mean annual incidence of VL decreased significantly from 1.88 before (1985-2000) to 0.77 per 1000 child population after the intervention (2001-07). In a control area with no surveillance, it increased from 0.11 to 0.23 per 1000. Early detection of VL using practical serological tests and timely treatment of cases could decrease the mortality and morbidity rates of VL in endemic areas.