| The incubation period is about 10 days to onset of | | | | sclerosing pan-encephalitis (SSPE), a fatal |
| fever and 14 days to appearance of rash. The | | | | degenerative brain disorder. The disease manifests |
| prodromal period is characterized by fever, sneezing, | | | | itself in children and young adults by progressive |
| coughing, running nose, redness or eyes. Koplik's | | | | mental deterioration, myoclonic jerks, and an |
| spots (enanthems of the buccal mucosa), and | | | | abnormal dectro-encephalogram with periodic high |
| lymphopenia. The fever and cough persist until the | | | | voltage complexes. The disease develops a number |
| rash appears and then subside within 1-2 days. The | | | | of years after the initial measles infection. |
| rash spreads over the entire body within 2-4 days, | | | | Laboratory Diagnosis |
| becoming brownish in 5-10 days. Symptoms of the | | | | Measles is usually easily diagnosed on clinical grounds. |
| disease are most marked when the rash is at its | | | | About 5% of cases lack Koplik's spots and are |
| peak but subside rapidly thereafter. | | | | difficult to differentiate clinically from infection with |
| In measles, the respiratory tract becomes more | | | | rubella virus, certain enteroviruses, and adenoviruses. |
| susceptible to invasion by bacteria, especially | | | | Recovery of Virus |
| hemolytic streptococci; bronchitis, pneumonia, and | | | | Measles virus can be isolated from the blood and |
| otitis may follow in 15% of cases. Encephalomyelitis | | | | nasopharynx of a patient from 2-3 days before the |
| occurs in about 1:1000 cases. There appears to be no | | | | onset of symptoms to 1 day after the appearance |
| correlation between the severity of the measles and | | | | of rash. Human amnion or kidney cell cultures are |
| the appearance of neurologic complications. The | | | | best suited for isolation of virus. |
| cause of measles encephalitis is unknown. It has been | | | | Serology |
| suggested that early central nervous system | | | | Specific neutralizing, hemagglutination-inhibiting and |
| involvement is caused by direct viral invasion of the | | | | complement-fixing antibodies develop early, with |
| brain. Later appearance of central nervous system | | | | maximal liters near the time of onset of rash. There |
| symptoms is associated with demyelination and may | | | | is only a gradual decline in antibody liter with age. |
| be an immuno-pathologic reaction. Symptoms | | | | Measles and canine distemper share an antigen. |
| referable to the brain usually appear a few days | | | | Measles patients develop antibodies that cross-react |
| after the appearance of the rash, often after it has | | | | with canine distemper virus. Similarly, dogs, after |
| faded. There is a second bout of fever, with | | | | infection with distemper virus, develop antibodies that |
| drowsiness or convulsions and pleocytosis of the | | | | fix complement with measles antigen. Rinderpest |
| cerebrospinal fluid. Survivors may show permanent | | | | virus is also to measles. |
| mental disorders (psychosis or personality change) or | | | | Immunity |
| physical disabilities, particularly seizure disorders. The | | | | There appears to be only one antigenic type of |
| mortality rate in encephalitis associated with measles | | | | measles virus, as one attack generally confers lifelong |
| is about 10-30% and many survivors (40%) show | | | | immunity. Most so-called second attacks represent |
| sequelae. | | | | errors in diagnosis of the initial or the second illness. |
| Measles virus appears to be responsible for sub-acute | | | | |