Measles, also known as rubeola is a viral infection of the respiratory system.
The disease is a very contagious disease and can spread through contact with infected mucus and saliva. It normally occurs in children in the tropics.
Most children in developing countries have it before the ages of 3-4 years. Children have some immunity for the first 6 months of life. And Wears off rapidly after that and by one year of age, a third (1/3) of children would have suffered from the disease. By age 3 years three quarters (¾) would have suffered from it.
Measles can be classified under suspected cases and confirmed cases.
Any person with fever and maculopapular (non-vesicular) generalized rash and cough, coryza or conjunction (red eyes) or any person in whom a clinician suspects measles.
A suspected case with laboratory confirmation (positive IgM antibody) or epidemiological link to confirmed cases in an outbreak.
The incubation period usually begins from 8 to 12 days after you are exposed to the virus.
Mode of Transmission
The highly contagious virus is spread by direct contact (through coughing, sneezing, or talking)
Direct contact with infected nasal or throat secretions.
Blood and urine of infected persons can also be a source of the infection.
90% of people without immunity sharing living space with an infected person will catch it.
The virus remains active and contagious in the air or on infected surfaces for up to 2 hours.
It can be transmitted by an infected person from 4 days prior to the onset of the rash to 4 days after the rash erupts.
Below is the life-cycle of Measles.
1.Portal of entry
The host absorbs the virus into the respiratory tract through inhalation
Hemagglutinin (H) and fusion protein (F) are components of the viral envelope which helps it to attach to the host epithelial cells in the upper respiratory tract.
H. binds to CD46 and CD150 cellular receptors.
It penetrates the cell surface and uncoat.
It injects RNA into the host cell’s cytoplasm
Synthesis of mRNA, translation, and replication all take place in the cytoplasm of the host cell.
Virion RNA polymerase transcribes the negative-strand genome to mRNA.
Specific viral proteins are formed and assembly to helical nucleocapsid.
5. Release and Transmission
The new virus is released by budding.
Transmission of the virus is by the droplet or airborne route.
The virus reinvades the epithelial cells of the upper respiratory tract of a new host who absorbs it.
After inial viral replication takes place in the respiratory epithelium, the virus moves to the local lymphatic tissue.
It replicates again in the lymph nodes and then from there disseminates widely to many different organ systems.
The virus can target the kidney, liver, gastrointestinal tract and skin. In each of these systems, the virus replicates in epithelial and endothelial cells as well as in macrophages.
The signs and symptoms are grouped into three (3) stages
- First stage
- Second stage
- Third stage
The first stage (Prodromal Stage)
This occurs about 2 to 4 days of infection with cold-like symptoms
Characterized by non-specific symptoms that may be confused with many other respiratory infections.
So identifying measles based on these alone can be diﬃcult.
- Coryza (running nose)
Small white spots may be apparent on the mucous membrane along the parotid duct in the mouth.
These spots are known as Koplik spots and precede the appearance of the rash by a couple of days.
The second stage (Eruptive Stage)
Also known as the end of the Prodromal Stage. The communicable period is between 4-5 days.
The rash is often the main symptom.
Characteristics of the rash;
Usually appears 3 to 5 days after the first signs of being sick.
The rash develops first on the face and then extends down to the trunk and finally extends out to the extremities.
May last 4-7 days. It usually starts on the head and spreads to other areas, moving down the body. May appear as flat, discolored areas (macules) and solid, red, raised areas (papules) that later join together
- Eruptive rash
- The pattern of the rash
- Convalescent period
Comes immediately following the second stage without taking medications.
The body produces immunity against the infection and life-me resistance (immunity) is developed.
Rashes change from red to brown aer several days
The third clinical-stage can take many forms.
It appears when immunosuppression caused by measles virus infection is so severe that secondary complications arise.
Severe diarrhea and pneumonia are the most common complications secondary to measles infection.
1. History and physical assessment
The clinical diagnosis of measles is based on the signs and symptoms presented.
History of fever of at least three days together with at least one of the three C’s (cough, coryza, conjunction).
Koplik’s spots seen inside the mouth are diagnostic for measles but are not often seen, even in real cases of measles, because they are transient and may disappear within a day of arising.
2. Measles serology
Isolation of measles virus from urine, nasopharynx, blood, throat
Significant rise in measles IgG by any standard serologic assay (e.g., EIA, HI)
Positive serologic test for measles IgM antibody
3. Viral culture (rarely done)
There is no specific treatment for measles.
The following may relieve symptoms:
- Antipyretics eg. Acetaminophen
- Cough suppressants
- Antibacterial for complications such as pneumonia
- Some children may need vitamin A supplements, which reduce the risk of death and complications
- Place hospitalized children in isolation during the contagious period.
- Assess skin eyes, and mucous membranes for Koplik spots, rash, and conjunctivitis.
- Assess for enlarged lymph nodes.
- Maintain bed rest during the acute phase of the illness.
Administer cooling measures and antipyretics for fever.
Administer cough suppressants as needed.
- Assess respiratory status (related to impaired airway management due to runny nose, cough, and potential for pneumonia),
- Use comfort measures: tepid, topical lotions, positioning,
- Irrigate eyes with saline to relieve itching. Do not use the antibiotic ointment in the eyes (ineffective due to the viral cause of conjunctivitis),
- Remind the child to keep his/her hands away from his/her eyes,
- Provide a quiet, dimly lit room for a child with photophobia and/or headache,
- Administer analgesics as needed for discomfort.
- Maintain hydration status with oral fluids (as tolerated) and/or IV fluids.
- Monitor intake and output.
- Provide diversional acvies especially for children who must remain in Isolation
- Dispose of infected linen in a proper container.
- Active immunization in childhood given at age of 9 months and 18 months.
- During the outbreak, it should be given at 6 months and repeated at one year.
- Measles vaccination campaigns are contributing to the reduction of child deaths from other causes.
- Avoid exposure as much as possible to infected persons.
- All personal hygiene measures