Mumps
Mumps is spread from person to person through contact with respiratory secretions, such as saliva from an infected person. When an infected person coughs or sneezes, the droplets aerosolize and can enter the eyes, nose, or mouth of another person. Mumps can also be spread by sharing eating utensils or cups. The virus can also survive on surfaces and then be spread after contact in a similar manner. A person infected with mumps is contagious from approximately seven days before the onset of symptoms until about eight days after symptoms start. The incubation period (time until symptoms begin) can be from 12–25 days, but is typically 16–18 days. 20-40 percent of persons infected with the mumps virus do not show symptoms, so it is possible to be infected and spread the virus without knowing it.
Mites of livestock
The clinical manifestation of infestation with psoroptic mites is usually called mange and sometimes scabies, but the skin disease of sheep caused by "Psoroptes ovis" is often known locally as sheep scab. This species may affect its hosts severely enough to reduce their gain in weight. Costs to farmers of controlling sheep-scab in Britain were at £8 million (US$12 million) annually in 2005. Transmission between hosts is readily accomplished by contagion during flocking contact and also on fomites such as scraps of sheep's wool because these relatively large and robust mites can survive for one to two weeks off their host. "Psoroptes ovis" infests the superficial layers of the skin. Irritation of the outer skin by the mite's mouthparts and saliva results in a complex form of cutaneous hypersensitivity and inflammatory exudation of serum and fresh cells. The mites feed on this moist exudate. The skin loses its hair (depilation) at the sites of infestation and this may be extensive. As a result of the movement of the mites into areas of fresh skin, large scabs accumulate on the raw skin left behind. The mites cause intense pruritus (itching). In cases of heavy infestations, the host grooms compulsively, aggravating the depilation, and it may become mentally distressed. "Psoroptes ovis" infests sheep worldwide and can be a serious welfare and animal-production problem for sheep farmers.
Infestations of cattle with mites of the similar genus "Chorioptes", in combination with "Sarcoptes" mite infestation, has been shown to cause a failure to gain body weight by 15.5 kg to 37.2 kg over a two-month period compared to cattle without the mites.