Roughly 50-75% of all pregnant women are immune to parvovirus B19 while the remainder of women are susceptible to mild illness. A majority of fetuses who do contract parvovirus B19 show either no significant symptoms or complete resolution of the virus. However, the following serious complications are rare but possible: miscarriage, stillbirth, fetal anemia, hepatic failure, and abnormal neurodevelopment outcome. In some cases, fetuses would develop hydrops fetalis due to congenital parvovirus B19. This condition was studied as a determinant of later fetal outcomes, such as miscarriage or perinatal death, in 2016 systematic review. The review showed that those born with parvovirus B19 that caused hydrops fetalis did have an association with higher mortality risk and higher risk of complications. While the potential consequences of erythema infectiosum can be quite serious in pregnancy, mothers can be tested for immunity via the presence of IgG and IgM antibodies.In addition to fetuses, parvovirus B19 infection and its effects has been studied in adults as well. The virus has also been associated with the development of neurological complications, as identified in a systematic review in 2014. This analysis included a total of 89 studies covering complications in both the central and nervous system such as encephalitis, meningitis, and peripheral neuropathy. However, the specific pathophysiology of these complications has yet to be discovered but the review does encourage the use of antibody testing to determine a patients risk. Infection of this virus is not limited to the nervous system.
Tafenoquine, sold under the brand name Krintafel among others, is a medication used to prevent and to treat malaria. With respect to acute malaria, it is used together with other medications to prevent relapse by Plasmodium vivax. It may be used to prevent all types of malaria. It is taken by mouth.Common side effects include vomiting, headache, and dizziness. Other side effects may include methemoglobinemia, trouble sleeping, and anaphylaxis. In people with G6PD deficiency, red blood cell breakdown may occur. Use in pregnancy is not recommended. Tafenoquine is in the 8-aminoquinoline family of medications. How it works is unclear but it is effective both in the liver and bloodstream. A possible mechanism of action and other novel perspectives have been published.Tafenoquine was approved for medical use in Australia and in the United States in 2018. Tafenoquine is related to primaquine. Medical use
Prevention
Tafenoquine may be used to prevent all types of malaria. For this use 200 mg 3 days before travel then 200 mg per week until one week after travel is recommended. Treatment
Tafenoquine is used for eliminating the hypnozoite stage of Plasmodium vivax and Plasmodium ovale that is responsible for relapse of these malarial infections, even when the blood stages are successfully cleared. Primaquine for 14 days can also be used for this. The advantage of tafenoquine is that it has a long half-life (2–3 weeks) and therefore a single treatment is sufficient. For this use, a single dose of 300 mg is recommended.