Zika virus is confirmed to be transmitted through breastfeeding through animal models
寨卡病毒,动物模型
z-bo
2020-07-23
660
Zika virus (ZIKV) infection is a major public health problem in the world. The World Health Organization has declared Zika virus a “public health emergency of international concern”. In 2015, Zika disease broke out in Brazil, where a large number of babies were born with developmental brain diseases related to the disease. Zika virus is mainly transmitted through mosquito bites, but it can also be transmitted sexually through infected semen. Studies have shown that after pregnant women are infected with ZIKV, the virus can infect the fetal brain through the placenta, causing fetal microcephaly. Recent clinical reports also show that ZIKV virus gene RNA fragments and infectious virus particles can be detected in the milk of mothers infected with ZIKV. There are also reports that after ZIKV was transmitted to breastfeeding mothers, newborns were infected with ZIKV, which raised concerns about the natural safety of breastfeeding. Therefore, important scientific questions are also raised. Can Zika virus infect babies through breast milk? It has not been clinically determined whether the infected infant ZIKV comes from breast milk, and there are no reports based on animal model studies to confirm the role of breast milk in the transmission of ZIKV.
Kunming Institute of Zoology, Chinese Academy of Sciences is the main research institute for animal models and human disease mechanisms, using type I interferon receptor knockout mice (IFNα/β receptor deficient mice, A129) and wild-type C57Bl6 mice. We have established And found an infection model, and found that ZIKV can infect newborn suckling mice through milk and cause neurological diseases and diseases in suckling mice. First, they established a natural breastfeeding model of ZIKV infection in suckling mice. ZIKV was injected intraperitoneally within 24 hours after delivery to infect female mice. It was found that high titers of infectious virus particles were detected in the milk of A129 female mice. After lactation, all lactating A129 mice were infected with ZIKV. However, the milk of wild-type C57B16 female mice does not contain infectious virus particles, and ZIKV cannot infect wild-type mammals through natural lactation. Later, they established a wild-type suckling mouse infection model with artificial breastfeeding. ZIKV was fed directly to wild-type breast-feeding mice through micro-feeding on the first day, and then healthy female mice were used to breast-feed the mice, and the infection of the breast-feeding mice was detected at different time points. It has been found that all wild-type suckling mice can be infected with ZIKV through artificial feeding and exhibit neurological symptoms. In natural or artificial breastfeeding models, ZIKV first replicates in the lung tissue of suckling mice and then spreads to other tissues and organs. Breast milk contains a large amount of antiviral active ingredients and may interfere with ZIKV infection. To further assess the risk of ZIKV infection in milk, they mixed breast milk with ZIKV virus and fed it to wild-type mammal mice through artificial feeding. They found that milk has certain anti-ZIKV activity, but it cannot prevent the spread of ZIKV.
