A Review of the Prevention of Mother-to-Child Transmission of Human T-Cell Lymphotrophic Virus Type 1 (HTLV-1) With a Proposed Management Algorithm.

Human T cell lymphotropic virus type 1 (HTLV-1) is a human retrovirus that is endemic in a number of regions across the world. There are an estimated 5-10 million people infected worldwide. Japan is currently the only country with a national antenatal screening programme in place. HTLV-1 is primarily transmitted sexually in adulthood, however it can be transmitted from mother-to-child perinatally. This can occur transplacentally, during the birth process or via breastmilk. If HTLV-1 is transmitted perinatally then the lifetime risk of adult T cell leukemia/lymphoma rises from 5 to 20%, therefore prevention of mother-to-child transmission of HTLV-1 is a public health priority. There are reliable immunological and molecular tests available for HTLV-1 diagnosis during pregnancy and screening should be considered on a country by country basis. Further research on best management is needed particularly for pregnancies in women with high HTLV-1 viral load. A first step would be to establish an international registry of cases and to monitor outcomes for neonates and mothers. We have summarized key risk factors for mother-to-child transmission of HTLV-1 and subsequently propose a pragmatic guideline for management of mothers and infants in pregnancy and the perinatal period to reduce the risk of transmission. This is clinically relevant in order to reduce mother-to-child transmission of HTLV-1 and it's complications.

Priorities for developing respiratory syncytial virus vaccines in different target populations.

The development of an effective vaccine against respiratory syncytial virus (RSV) has been hampered by major difficulties that occurred in the 1960s when a formalin-inactivated vaccine led to increased severity of RSV disease after acquisition of the virus in the RSV season after vaccination. Recent renewed efforts to develop a vaccine have resulted in about 38 candidate vaccines and monoclonal antibodies now in clinical development. The target populations for effective vaccination are varied and include neonates, young children, pregnant women, and older adults. The reasons for susceptibility to infection in each of these groups may be different and, therefore, could require different vaccine types for induction of protective immune responses, adding a further challenge for vaccine development. Here, we review the current knowledge of RSV vaccine development for these target populations and propose a view and rationale for prioritizing RSV vaccine development.