Imported cases of Chikungunya virus in Iran

Mohammad Hassan Pouriayevali (1) , Farshid Rezaei (2) , Tahmineh Jalali (1) , Vahid Baniasadi (1) , Mehdi Fazlalipour (1) , Ehsan Mostafavi (1) , Sahar Khakifirouz (1) , Tahereh Mohammadi (1) , Zahra Fereydooni (1) , Mahsa Tavakoli (1) , Sanam Azad-Manjiri (1) , Motahareh Hosseini (1) , Mahsa Ghalejoogh (1) , Mohammad Mehdi Gouya (2) , Anna-Bella Failloux (3) , Mostafa Salehi-Vaziri (1, 1)

1 Institut Pasteur d'Iran
2 Centre for Diseases Control and Prevention [Iran]
3 Arbovirus et Insectes Vecteurs - Arboviruses and Insect Vectors

BACKGROUND: Chikungunya virus (CHIKV) is a widespread mosquito-borne virus representing a serious challenge to public health. The largest outbreak in the Middle-East was recorded in 2016-2017 in Pakistan. Sistan and Baluchistan Province of Iran shares a wide border with Pakistan; accordingly, introduction of CHIKV from Pakistan to Iran seems to be probable. The current study is aimed at investigating CHIKV infection in Sistan and Baluchistan Province. METHODS: Between April 2017 and June 2018, a total of 159 serum samples of CHIK suspected cases from 10 cities of Sistan and Baluchistan Province were tested by molecular and serological assays. Samples obtained up to 4 days after onset of illness were tested by real time PCR (n = 8). Samples collected 5-10 days after disease onset were subjected to ELISA, as well as real time PCR tests (n = 72). Samples obtained after the 10th day of disease onset were tested by only ELISA (n = 79). Phylogenetic analysis of real time PCR positive samples was carried out by sequencing of a 1014-bp region of Envelope 1 gene (E1 gene). Chi-square and independent t tests were used to evaluate the association between variables and CHIKV infection. RESULTS: In total, 40 (25.1%) out of 159 samples tested positive either by real time PCR or ELISA tests.Out of 151 samples serologically analyzed, 19 (12.6%) and 28 (18.6%) cases were positive for anti-CHIKV IgM and anti-CHIKV IgG antibodies, respectively. Of 80 samples tested by real time PCR, CHIKV RNA was detected in 11 (13.7%) sera, all of them had recent travel history to Pakistan. Additionally, phylogenetic analysis of 5 samples indicated their similarity with recent isolates of Pakistan outbreak 2016-2017 belonging to Indian Ocean sub-lineage of ECSA genotype. A significant correlation between abroad travel history and CHIKV infection was observed (P < 0.001). The most common clinical symptoms included fever, arthralgia/arthritis, myalgia, headache, and chill. CONCLUSIONS: These results present substantial evidence of CHIKV introduction to Iran from Pakistan and emphasize the need for the enhancement of surveillance system and preventive measures.

Mots clés: Pakistan; Chikungunya; Imported case; Iran

Domaines: Virologie

Mohammad Hassan Pouriayevali, Farshid Rezaei, Tahmineh Jalali, Vahid Baniasadi, Mehdi Fazlalipour, et al.. Imported cases of Chikungunya virus in Iran. BMC Infectious Diseases, 2019, 19 (1), pp.1004. ⟨10.1186/s12879-019-4637-4⟩. ⟨pasteur-02434662⟩