Fu, Jolene Yin Ling and Chua, Chong Long and Abu Bakar, Athirah Shafiqah and Vythilingam, Indra and Sulaiman, Wan Yusoff Wan and Alphey, Luke and Chan, Yoke Fun and Sam, I-Ching (2023) Susceptibility of Aedes albopictus, Ae. aegypti and human populations to Ross River virus in Kuala Lumpur, Malaysia. PLoS Neglected Tropical Diseases, 17 (6). ISSN 1935-2735, DOI https://doi.org/10.1371/journal.pntd.0011423.
Full text not available from this repository.Abstract
BackgroundEmerging arboviruses such as chikungunya and Zika viruses have unexpectedly caused widespread outbreaks in tropical and subtropical regions recently. Ross River virus (RRV) is endemic in Australia and has epidemic potential. In Malaysia, Aedes mosquitoes are abundant and drive dengue and chikungunya outbreaks. We assessed risk of an RRV outbreak in Kuala Lumpur, Malaysia by determining vector competence of local Aedes mosquitoes and local seroprevalence as a proxy of human population susceptibility. Methodology/Principal findingsWe assessed oral susceptibility of Malaysian Ae. aegypti and Ae. albopictus by real-time PCR to an Australian RRV strain SW2089. Replication kinetics in midgut, head and saliva were determined at 3 and 10 days post-infection (dpi). With a 3 log(10) PFU/ml blood meal, infection rate was higher in Ae. albopictus (60%) than Ae. aegypti (15%; p<0.05). Despite similar infection rates at 5 and 7 log(10) PFU/ml blood meals, Ae. albopictus had significantly higher viral loads and required a significantly lower median oral infectious dose (2.7 log(10) PFU/ml) than Ae. aegypti (4.2 log(10) PFU/ml). Ae. albopictus showed higher vector competence, with higher viral loads in heads and saliva, and higher transmission rate (RRV present in saliva) of 100% at 10 dpi, than Ae. aegypti (41%). Ae. aegypti demonstrated greater barriers at either midgut escape or salivary gland infection, and salivary gland escape. We then assessed seropositivity against RRV among 240 Kuala Lumpur inpatients using plaque reduction neutralization, and found a low rate of 0.8%. Conclusions/SignificanceBoth Ae. aegypti and Ae. albopictus are susceptible to RRV, but Ae. albopictus displays greater vector competence. Extensive travel links with Australia, abundant Aedes vectors, and low population immunity places Kuala Lumpur, Malaysia at risk of an imported RRV outbreak. Surveillance and increased diagnostic awareness and capacity are imperative to prevent establishment of new arboviruses in Malaysia. Author summaryRoss River virus (RRV) is transmitted by mosquitoes and causes outbreaks of fever and joint pain in endemic regions of Australia and some Pacific islands. Arboviruses may spread globally if infected travellers are bitten by potential mosquito vectors in previously unaffected countries with highly susceptible human populations. Aedes aegypti and Ae. albopictus mosquitoes have not been incriminated as natural RRV vectors, but are highly prevalent in Malaysia and spread other arboviruses such as dengue virus. We showed that Malaysian Ae. aegypti and Ae. albopictus could potentially transmit RRV from as early as 3 days after an infectious blood meal. Ae. albopictus demonstrates higher vector competence for transmitting RRV than Ae. aegypti, as it can be infected with lower oral doses, displays higher transmission rates in saliva (100% by 10 days), and higher viral loads in heads and saliva. We tested 240 patient blood samples from Kuala Lumpur, Malaysia and found only a small proportion (0.8%) had neutralizing antibodies against RRV. In summary, Malaysia is at risk of an RRV epidemic due to presence of a naive host population and abundant competent mosquito vectors. Surveillance efforts and epidemic preparedness should include RRV.
| Item Type: | Article |
|---|---|
| Funders: | Universiti Malaya (RK015-2021), Wellcome Trust (200171/Z/15/Z) |
| Subjects: | R Medicine > R Medicine (General) |
| Divisions: | Faculty of Medicine > Medical Microbiology Department Faculty of Medicine > Parasitology Deparment |
| Depositing User: | Ms. Juhaida Abd Rahim |
| Date Deposited: | 29 Jul 2025 04:29 |
| Last Modified: | 29 Jul 2025 04:29 |
| URI: | http://eprints.um.edu.my/id/eprint/50761 |
Actions (login required)
 |
View Item |
