Parotid gland
Mumps is seen to be a common cause of parotid gland swelling - 85% of cases occur in children younger than 15 years. The disease is highly contagious and spreads by airborne droplets from salivary, nasal, and urinary secretions. Symptoms include oedema in the area, trismus as well as otalgia. The lesion tends to begin on one side of the face and eventually becomes bilateral. The transmission of the paramyxovirus is by contact with the infected persons saliva. Initial symptoms tend to be a headache and fever. Mumps is not fatal, however further complications can include swelling of the ovaries or the testes. Diagnosis of mumps is confirmed through viral serology, management of the condition includes hydration and good oral hygiene of the patient requiring excellent motivation. However, since the development of the mumps vaccine, given at the age of between 4–6 years, the incidence of this viral infection has greatly reduced. This vaccine has reduced the incidence by 99%.
Lymphocytic choriomeningitis
LCMV infections are focal Estimates of its prevalence in wild mouse populations range from 0% to 60%, with an average prevalence of 9%. The incidence of LCMV in pet rodents is unknown, yet very few human cases have been associated with exposure to pets. In the transplant-associated cases linked to a pet hamster in 2005, two other hamsters and a guinea pig at the pet shop, and approximately 4% of the hamsters at the distributor, were also infected. Morbidity and mortality rates vary with the species of animal and its age at infection, as well as the strain of the virus and route of exposure. Neonatally and congenitally infected mice remain asymptomatic for many months, but the onset of glomerulonephritis reduces overall life expectancy. The morbidity rate in naturally infected post-neonatal mice is unknown; however, subclinical disease may be the most common form, as few natural outbreaks have been reported. In hamsters, approximately half of all congenitally infected animals clear the virus when they are approximately three months old and remain healthy; the remaining animals develop chronic disease. Hamsters infected as adults usually remain asymptomatic. Callitrichid hepatitis is reported to be highly fatal in naturally infected marmosets and tamarins in zoos. Since 1980, 12 outbreaks with 57 deaths have been reported in the U.S. In experimentally infected rhesusmacaques, three of four animals became fatally ill when inoculation was by the intravenous route. In contrast, inoculation by the intragastric route usually led to asymptomatic infections, with occasional disease and few deaths.