Rady Magda H, Ammar Asmaa M, Salama Mohamed S, Farag Shaimaa M
Entomology Department, Faculty of Science, Ain Shams University, Cairo, Egypt.
Medical Parasitology Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt.
Trop Med Int Health. 2025 Sep 2. doi: 10.1111/tmi.70025.
Dengue fever poses a significant public health threat in tropical regions, with Aedes aegypti as the primary vector. This study investigated dengue virus prevalence and serotype distribution in field-collected Ae. aegypti mosquitoes across the Red Sea governorate during 2023-2024.
A surveillance study was conducted across five districts (Shoaib, Al-Garf, Al-Owaina, Al-Odwa and Al-Ashraaf) from April 2023 to March 2024. A total of 1330 adult females Ae. aegypti mosquitoes were organised into 133 pools for molecular analysis. Molecular identification using mitochondrial cytochrome oxidase I and internal transcribed spacer 2 markers were used to assure the presence of Aedes vector. Dengue virus RNA detection employed nested RT-PCR with serotype-specific amplification.
All specimens were confirmed as Ae. aegypti with characteristic cytochrome oxidase I (714 bp) and internal transcribed spacer 2 (313 bp) amplification products and morphological examinations. Dengue virus RNA was detected in 13 adults out of 1330 females from all visited districts, with total MIR estimated as 0.97. Al-Odwa district showed the highest infection rate (1.3) followed by Shoaib (0.83), Al-Owaina and Al-Garf (1), while Al-Ashraaf had the lowest percentage (0.4). Peak viral activity occurred in December 2023 across all districts, with no summer detections (June-September 2023). Three serotypes circulated in our habitat: DENV-2 (all five districts), DENV-1 (four districts) and DENV-3 (Al-Odwa only). DENV-4 was absent. Four districts showed DENV-1/DENV-2 co-circulation, while Al-Odwa uniquely harboured DENV-2/DENV-3.
This study demonstrates active dengue virus circulation in Red Sea governorate with distinct spatial-temporal patterns. The identification of three co-circulating serotypes with geographic variation highlights regional epidemiological complexity. Seasonal patterns suggest that environmental influences affect transmission dynamics, providing crucial baseline data for targeting surveillance and control strategies.
登革热在热带地区对公共卫生构成重大威胁，埃及伊蚊是主要传播媒介。本研究调查了2023 - 2024年红海省野外采集的埃及伊蚊中登革病毒的流行情况和血清型分布。
2023年4月至2024年3月在五个区（绍艾卜、加尔夫、奥瓦伊纳、奥德瓦和阿什拉夫）开展了一项监测研究。总共1330只成年雌性埃及伊蚊被分成133组进行分子分析。使用线粒体细胞色素氧化酶I和内部转录间隔区2标记进行分子鉴定，以确保埃及伊蚊传播媒介的存在。登革病毒RNA检测采用巢式逆转录聚合酶链反应及血清型特异性扩增。
所有标本经特征性细胞色素氧化酶I（714 bp）和内部转录间隔区2（313 bp）扩增产物及形态学检查，均确认为埃及伊蚊。在所有走访地区的1330只雌性伊蚊中，有13只成虫检测到登革病毒RNA，总感染率估计为0.97。奥德瓦区感染率最高（1.3），其次是绍艾卜（0.83）、奥瓦伊纳和加尔夫（1），而阿什拉夫区感染率最低（0.4）。2023年12月所有地区出现病毒活动高峰，2023年6月至9月夏季未检测到病毒。三种血清型在我们的栖息地传播：登革病毒2型（所有五个区）、登革病毒1型（四个区）和登革病毒3型（仅奥德瓦区）。未检测到登革病毒4型。四个区出现登革病毒1型/登革病毒2型共同传播，而奥德瓦区独特地同时存在登革病毒2型/登革病毒3型。
本研究表明红海省登革病毒呈活跃传播，具有明显的时空模式。三种共同传播血清型及其地理差异的鉴定凸显了该地区流行病学的复杂性。季节性模式表明环境影响传播动态，为针对性监测和控制策略提供了关键的基础数据。
