Amenorrhoea is a symptom with many potential causes. Primary amenorrhoea (menstrual cycles never starting) may be caused by developmental problems such as the congenital absence of the uterus, failure of the ovary to receive or maintain egg cells. Also, delay in pubertal development will lead to primary amenorrhoea.
Diseases transmitted by mosquitoes include: malaria, dengue, West Nile virus, chikungunya, yellow fever, filariasis, Japanese encephalitis, Saint Louis encephalitis, Western equine encephalitis, Eastern equine encephalitis, Venezuelan equine encephalitis, La Crosse encephalitis and Zika fever.
They can also carry the virus for yellow fever and dengue fever. More rare viral diseases such as Rift valley fever or the West Nile virus are also carried by some species of mosquitoes.