Obstetrics & Gynaecology Forum Volume 29 | Issue 3 | 2019

Measles in pregnancy Correspondence Dr S. Mayosi email: vuyimayosi@yahoo.com Measles is also known as Rubeola 1 . Humans are the common host for the virus where it is found in the pharyngeal and nasal mucosa. e virus is transmitted via droplet spread or contact with an infected sur- face and then touching one’s nose, eyes or mouth 2 . It can survive up to two hours in the air 3 . Measles is highly infectious and 90% of individ- uals who are not immunized that come into contact with an infected patient, will become infected 2,3 . e following are regarded as high risk individuals for measles infection: children under 5 years, adults above 20 years of age, pregnant women, immune compromised individuals, and those with malnutrition or Vitamin A de ciency 1,2,3 . Measles virus is a negative strand RNA virus of the Paromyxovir- idae family 4 . e virus enters the respiratory tract, where it binds to dendrocytes and infects CD150 + myeloid or lymphoid cells in the mu- cocillary epithelium, alveolar spaces or the conjunctiva. e infected immune cells then migrate to the nearby tertiary lymphoid tissues or are drained by nearby lymph nodes 4 . Primary lymphoid tissues such as the bone marrow and thymus, secondary lymphoid tissues, such as spleen, tonsils and lymph nodes and tertiary lymphoid tissues such as bronchus associated lymphoid tissue, are where measles virus replica- tion takes place. ese tissues are rich in CD 150 + lymphocytes 4 . Dis- semination of measles virus occurs largely by cell to cell transmission. When viraemia occurs, infected cells enter circulation and migrate to various organs and tissues such as the skin, liver, gastrointestinal tract and kidneys. It rarely infects endothelial cells, neurons and astrocytes 4 . When the skin is infected, for example, dermoid endothelial cells and keratinocytes are thought to be infected. e infection is subsequently cleared by the Measles Virus- Speci c T-cells, which gives the appear- ance of a rash 4 . e period an individual is contagious for, is from 4 days before the onset of the rash until 4 days a er the rash disappears 2 . In the case of immune compromised individuals, they may not develop a rash 2 . e measles virus incubation period is 7 to 21 days 1,5 . e symp- toms of measles typically occur day 7 – 14 a er the individual becomes infected. e rst symptoms and signs are a high fever, cough, coryza and conjunctivitis 2 . Two to three days later small white spots may appear on the inside of the mouth, these are called Koplik spots 2 . Koplik spots are described as bluish grey specks and they usually develop opposite the second molars. Between day 3 to 7 the classical skin rash will appear 2,6 . e lesions are associated with mild pruritis. Usually 48 hours a er the lesions appear, they coalesce to form patches or plaques 6 . e lesions tend to spread cephalocaudally and the density is greatest above the shoulders 2 . e lesions may be ecchymotic or petechial. A er 5 to 7 days they change into coppery-brown hyperpig- mented patches which then desquamate 6 . Measles causes host immune suppression and this results in su- perinfection or reactivation of other latent infections 6 . e common complications in the general population include pneumonia, croup, otitis media, exacerbation of tuberculosis, sinusitis, stomatitis, subclin- ical hepatitis, lymphadenitis, keratitis and diarrhoea 1,6 . Rare com- plications include encephalitis, hearing loss, haemorrhagic measles, purpura fulminans, hepatitis, disseminated intravascular coagulation, subacute sclerosing panencephalitis, thrombocytopenia, appendicitis, ileocolitis, pericarditis, myocarditis, acute pancreatitis, hypocalcaemia and death 1,6 . e causes of death are usually due to pneumonia, croup and meningitis. Young children, infants and immune compromised patients are at risk of the rare complications. If a pregnant woman contracts measles, she is at risk of miscarriage, stillbirth, and preterm delivery, however fetal anomalies have not been described. e infant may be born low birth weight or have congenital measles if the mother has an active measles infection 1,5 . With the worldwide reluctance to immunize there is an increased risk of pregnant women getting infected with measles infection 3 . Between 1st January to 11 th April 2019, there have been 555 cases of measles reported in the United States of America, as well as multiple outbreaks reported worldwide. ‘Measles virus remains the leading cause of vaccine-preventable illness and death worldwide’ 3 . e diagnosis of measles depends on the triad of cough, coryza and conjunctivitis 6 . e di erential diagnosis of measles include the follow- ing: Kawasaki disease, Dengue fever, serum sickness, syphilis, systemic lupus erythematosus, toxic shock syndrome, acute conjunctivitis, dermatological manifestations of viral haemorrhagic fever, drug erup- tions, Epstein-Barr Virus infectious mononucleosis, meningitis, Parvo B19 infection 6 . It is o en su cient to make the diagnosis based on the clinical ndings, but for public health considerations or to con rm the diagnosis, samples should be sent. e laboratory diagnosis of measles includes blood for measles IgG and IgM antibodies, viral isolation from nasal or throat swabs, as well as urine, using reverse-transcriptase PCR of the viral RNA 4,5 . Measles speci c IgG antibody or ELISA (En- zyme-linked immunosorbent assay) may be used to assess immunity 1 . If positive, at any titre, consider immune. e IgG will become positive four days a er the rash started and a four-fold raise in the IgG is diag- nostic 2,5 If negative, one would ideally go on to do a Plaque reduction neutralization test (PRNT) which is the gold standard. As there is signi cantly less sensitivity in the serologic assays 1 . PRNT is not always readily available and is expensive. Recent Measles infection can be assessed by testing Measles speci c IgM on serum taken more than 4 days but within 1 month of the onset of the rash. A full blood count may show leukopenia with a lymphocytosis and low platelets 6 . e transaminases may be raised if the patient has hepatitis. If meningitis or pneumonia is suspected a lumbar puncture or chest X-Ray should be performed respectively 6 . Preventing measles in pregnancy can be achieved by administering either the measles or MMR vaccine to all women who have not had measles previously or who have not received either the stand alone measles vaccine or combined MMR vaccine. Currently the EPI Sched- ule in South Africa includes the measles vaccine at 6 and 12 months of age which will protect 95% of people 7 . e MMR vaccine has to be sourced privately. e measles vaccine is a live attenuated vaccine with a theoretical risk of harm to mother and fetus 1 . It is advisable Dr S. Mayosi 1 , Prof H. Lombaard 1,2 , Dr A. Wise 1,2 1 Department Obstetrics and Gynaecology, Rahima Moosa Mother and Child Hospital, Johannesburg, South Africa 2 Department of Obstetrics and Gynaecology, University of the Witwatersrand, Johannesburg, South Africa O&G Forum 2019; 29: 12 - 13 REVIEW OBSTETRICS & GYNAECOLOGY FORUM 2019 | ISSUE 3 | 12