Updated: May 18, 2007
Measles has been called the greatest killer of children in history. Despite the availability of an effective vaccine that was developed more than 30 years ago, the measles virus still affects 50 million people annually and causes more than 1 million deaths. The highest incidence of measles and its associated morbidity and mortality is observed in developing countries. However, it still occurs infrequently in the United States and other industrialized nations.
Instead of replicating in the respiratory epithelium, as was once thought, replication appears to occur in the regional lymph nodes. Replication in regional lymph nodes eventually leads to viremia. Infection of the endothelial cells ensues, causing an enanthem (Koplik spots). Epithelial cells are also infected, leading to the well-known cutaneous eruption of measles.
The measles virus is a single stranded RNA virus of the genus Morbillivirus and family Paramyxoviridae. Measles virus has 2 membrane glycoproteins called hemagglutinin and fusion. Both of these glycoproteins appear to be important for infection with the measles virus. Hemagglutinin appears to be involved with receptor binding and fusion, with fusion of the virus with host cells. Expression of hemagglutinin activates the alternative complement pathway.
The Edmonston strain of the measles virus and vaccines derived from this strain bind to the cell surface protein CD46, also known as membrane cofactor protein. CD46 is a regulator of the complement activation gene and inhibits activation of the alternative complement pathway. Four isoforms of CD46 exist in humans, and all are capable of binding measles virus.
An additional cellular receptor for the measles virus has recently been identified called SLAM (signaling lymphocyte-activation molecule) or CDw150 expressed on some T and B cells. SLAM is capable of binding strains of the measles virus that also bind CD46 (the Edmonston strain) as well as strains that do not bind CD46 such as the KA strain.
Infection with the measles virus leads to a prolonged immunosuppression, which accounts for much of the morbidity and mortality associated with this disease. Cell-mediated immunity decreases, clinically evidenced by the conversion of positive tuberculin skin test results to negative following infection or vaccination. The mechanism of this immunosuppression is being elucidated.
Following infection with the measles virus, a shift from cell-mediated immunity (a TH-1 response) to humoral immunity (a TH-2 response) occurs. Expression of the TH-2 cytokine interleukin (IL)–2 is increased, supporting antibody formation, and TH-1 cytokines IL-2, IL-12, interferon (IFN)–gamma decrease.
IL-12 is a crucial cytokine for the development of cell-mediated immunity. It is necessary for delayed-type hypersensitivity, induces production of IFN-gamma, and plays a role in activation of T cells and natural killer cells. Karp et al1 found that infection of monocytes, the primary producer of IL-12, with the measles virus via CD46 led to decreased production of this cytokine. Fugier-Vivier et al2 found that activated dendritic cells also had a significant decrease in production of IL-12, leading to proliferation of the measles virus and apoptosis of infected dendritic cells and T cells. These findings support the hypothesis that measles virus infection of antigen-presenting cells plays a critical role in the immunosuppression observed following infection with the measles virus.
Primates are the only hosts for measles virus, and no animal model exists that replicates the clinical findings of measles infection typical in children.
The US Centers for Disease Control and Prevention (CDC) support strict surveillance of measles both in the United States and abroad. The CDC defines a case of measles as one that is confirmed by (1) serologic laboratory tests, such as enzyme immunoassays for measles IgM antibodies; (2) cases epidemiologically linked to a laboratory confirmed case; or (3) clinically confirmed cases (ie, cases of measles suspected clinically but neither confirmed by serologic laboratory tests nor epidemiologically linked to a laboratory confirmed case). In countries that are trying to eliminate measles, the category of clinically confirmed cases represents a failure of the surveillance system because all cases ideally should be confirmed serologically or epidemiologically linked to a laboratory confirmed case.
According to an epidemiologic report by the CDC in 19993 , the measles virus is no longer indigenous to the United States. Most reported measles cases are importation associated, meaning that they are linked to a strain of the measles virus outside of the United States.
In 2005, the CDC reported that 66 cases of measles were confirmed in the United States. Fifty of these cases were in unvaccinated individuals and 17 were contracted while traveling abroad. A large outbreak in Indiana in 2005 infected 34 people, the largest outbreak since 1999. This outbreak was linked to a young woman who acquired the infection while on a brief trip (2 wk) to Romania. As recently as June 2006, a measles outbreak occurred in Boston, Mass and was linked to a recent immigrant from India. Thirteen cases of measles were confirmed in this outbreak, and they were linked to a common Indian strain of this virus.
More concerning was the report of 2 infected individuals who worked at the ChristianScienceCenter in downtown Boston. Many members of this church are unvaccinated, which raised concern that the virus would spread further.
Importation-associated strains of measles may be acquired outside of the United States (internationally imported), have a known chain of transmission from an internationally imported source (epi-linked), or have a genotype that matches a known international strain without a clear chain of transmission or individual source (imported).
The number of non–importation-associated measles cases has significantly decreased since 1995, when 85% of all reported cases of measles in the United States were considered indigenous and not linked to importation. In addition, only 6 measles outbreaks were reported in 1998, the lowest ever recorded. The data collected by the CDC suggest that indigenous measles has been eliminated in the United States. Despite this, cases of measles will continue to arise, as it is not as well controlled in other parts of the world.
Cases of measles will continue to arise even in developed nations with a high percentage of vaccinated individuals because of the millions of people still infected worldwide. Vaccination campaigns in many developing nations have fallen short, making measles deaths the most common cause of childhood death from vaccine-preventable disease. In the World Health Report in 2002, the World Health Organization (WHO) reported 30-40 million cases of measles annually, with 745,000 deaths attributable to the virus. In Africa in the 1990s, an estimated 400,000 children died annually from complications related to measles.
Infection with measles has no race predilection. Prevalence is linked to inadequate vaccination in developing countries.
Measles infection has no sex predilection.
Historically, measles is a disease of childhood and continues to affect children in developing countries. In industrialized nations, infection is seen in unvaccinated individuals of any age or those with waned immunity.
Measles was the first exanthem described historically.
See Pathophysiology.
Drug Eruptions
Gianotti-Crosti Syndrome (Papular Acrodermatitis
of Childhood)
Hypersensitivity Vasculitis (Leukocytoclastic
Vasculitis)
Kawasaki Disease
Rubella
Syphilis
Exanthems usually associated with systemic lymphadenopathy
Brucellosis
Cytomegalovirus
Gianotti-Crosti syndrome
HIV (primary)
Mononucleosis + ampicillin or allopurinol
Kawasaki disease
Rubella (German measles)
Syphilis (congenital, secondary)
Toxoplasmosis
Anticonvulsant hypersensitivity syndrome
Skin biopsy of the fully evolved exanthem of measles is not specific, but the findings can be suggestive of the diagnosis. The histologic findings include psoriasiform epidermal hyperplasia, spongiosis, parakeratosis, and occasional dyskeratotic keratinocytes. Multinucleated keratinocytes (Warthin-Finkeldey giant cells) may be seen. A superficial, perivascular lymphocytic infiltrate associated with variable erythrocyte extravasation is present in the dermis. Multinucleated lymphoid cells containing intranuclear and cytoplasmic inclusions may be observed.
Treatment for measles generally consists of only supportive care, with particular attention to maintaining good hydration, especially in the developing world. Recently, however, the WHO has also recommended that vitamin A supplementation be given with measles vaccination in the developing world. The impetus behind this recommendation stems from the fact that a precipitous decrease occurs in vitamin A levels, which may already be low in children who are malnourished, at the onset of the exanthem. By giving a bolus of vitamin A with the vaccine, the WHO hopes to attenuate some of the complications (eg, blindness) associated with vitamin A deficiency. Antibiotics are indicated with diagnosed or suspected secondary bacterial infection but are not empirically indicated.
Infected individuals or those suspected to have infection with the live measles virus should be quarantined until they are no longer contagious to prevent spread of the disease to other nonimmunized individuals.
Vitamin A supplementation has been recommended in developing nations because of the higher rate of blindness following measles infection in malnourished individuals.
Preparation
In the United States, the measles vaccine is given in suite with mumps and rubella. Grown in chick fibroblast cell culture, the vaccine contains neomycin, sorbitol, and gelatin. Measles vaccine is both heat sensitive and light sensitive. Once reconstituted, its potency decreases each hour by 50% at 22-25°C, and it is completely inactivated at 37°C. This characteristic of the measles vaccine is important to consider both in the United States and abroad and may be responsible for decreased effectiveness of vaccine programs in developing countries with hot climates, particularly in areas where refrigeration may not be available. The measles vaccine should be stored at 2-8°C (35.6-46.4°F) and protected from light exposure. Once it has been reconstituted, the vaccine should be discarded after 8 hours.
Vaccine-related epidemiology
In the preimmunization era, approximately 130 million cases of measles and 7-8 million measles-related deaths occurred around the world each year (child mortality rate, 7%). However, by 1991, 80% of the world's children were immunized by age 1 year, and an estimated 1 million lives are saved annually with immunization. Despite this marked improvement, the WHO estimated that, in 1994, 45 million cases of measles and 1.19 million measles-related deaths still occurred, primarily in the developing world. Before the advent of the vaccine, measles primarily affected preschool-aged and young school-aged children. In the postvaccine era in industrialized nations, the age of children affected by measles has increased. By 1980, 60% of all cases of measles occurred in children older than 10 years. In developing countries, a different trend has been observed. The age of children infected has decreased, likely because the passive immunity from the mother wanes earlier in these countries.
Vaccine schedule
The difference in the age of children at risk for measles in the developed world versus the developing world has led to unique vaccination schedules aimed at serving the needs of these different communities. Although the best time for vaccination is debated, the following schedules are generally used: 2 doses in industrialized nations at age 12-15 months and age 11-12 years and 3 doses in developing countries starting at age 6-9 months, then at age 15 months, and repeated again upon entry into kindergarten.
One of the major complications with giving the vaccine at such an early age in the developing world is that the child may still have circulating antibodies from the mother. These antibodies can bind vaccine antigen prior to stimulating the child's own immune response and result in primary vaccine failure. Once this passive immunity wanes completely, the child has no protection against infection. This complication led health officials to recommend repeating the injection at age 15 months. Nonetheless, infection can occur within this window.
In industrialized nations, this schedule should be changed in some instances. For example, during outbreaks of measles in the United States or if an infant is traveling to an area where measles is endemic, the child should be vaccinated as young as age 6 months and then the regular schedule for industrialized nations should be followed.
Another indication for the vaccine is postexposure prophylaxis. Some evidence suggests that the vaccine may provide protection in susceptible persons exposed to the virus if the vaccine is given within the first 72 hours of known exposure. The measles vaccine, although live, is not communicable. Therefore, vaccination in all persons in contact with individuals who are immunocompromised is important in preventing the spread of natural disease to these patients.
Vaccine efficacy
Antibody titers following vaccination are lower than those following natural disease. However, 93% of children vaccinated at age 12 months and 98% of those vaccinated at age 15 months develop immunity to measles. Furthermore, more than 99% of children who receive 2 doses of the vaccine at least 1 month apart and after 12 months develop an appropriate response. Protective titers can last as long as 16 years.
The greatest advance against measles in the last 30 years has certainly been in prevention rather than treatment. The measles virus was first isolated in 1954 by Enders and Peebles, and the first live-attenuated vaccine, the Edmonston B strain, became available in the mid-to-late 1960s. The Moraten strain is the attenuated measles virus used in the United States today.
For anyone born in or after 1957 without documentation of live vaccine immunization on or after his or her first birthday.
0.5 mL SC in outer aspect of upper arm
<15 months: Not established
>15 months: Administer as in adults
Corticosteroids and other drugs that suppress immune system may diminish response to immunization
Documented hypersensitivity (contraindicated in individuals with life-threatening allergic reactions to neomycin and gelatin; patients who are immunocompromised; within 3 mo of cessation of immunosuppressive drugs; thrombocytopenia purpura with previous measles vaccine; tuberculin skin test (PPD results can be falsely negative up to 6 wk following measles vaccination); children who are allergic to eggs (generally considered safe even in individuals with egg allergy [discuss with your physician]); not recommended during or 3 mo prior to pregnancy, although no evidence of harm to fetus or mother has been documented
X - Contraindicated in pregnancy
Contraception in females is advised for 3 mo following immunization; not indicated for patients who are immunocompromised; skin testing of children allergic to eggs prior to vaccination is unreliable
Adverse reactions include fever >39.4°C 5-10 d following vaccine (10%), transient rash (5-15%), thrombocytopenia (occurs in 1 per 30,000-40,000 persons and is usually subclinical but may cause purpuric lesions), and encephalitis/encephalopathy (rare, <1 case per 1 million vaccinations)
Defer vaccination for at least 3 mo following blood or plasma transfusions or the administration of immune globulin; caution in history of cerebral injury, individual or family history of convulsions, or any condition in which stress due to fever should be avoided; should ensure that injection does not enter blood vessel; recent review of available data suggest that subacute sclerosing encephalopathy can be seen with measles infection, but not seen with vaccine
Karp CL, Wysocka M, Wahl LM, Ahearn JM, Cuomo PJ, Sherry B, et al. Mechanism of suppression of cell-mediated immunity by measles virus. Science. Jul 12 1996;273(5272):228-31. [Medline].
Fugier-Vivier I, Servet-Delprat C, Rivailler P, Rissoan MC, Liu YJ, Rabourdin-Combe C. Measles virus suppresses cell-mediated immunity by interfering with the survival and functions of dendritic and T cells. J Exp Med. Sep 15 1997;186(6):813-23. [Medline].
Centers for Disease Control and Prevention. Epidemiology of measles--United States, 1998. MMWR Morb Mortal Wkly Rep. Sep 3 1999;48(34):749-53. [Medline]. [Full Text].
Borrow P, Oldstone MB. Measles virus-mononuclear cell interactions. Curr Top Microbiol Immunol. 1995;191:85-100. [Medline].
Centers for Disease Control and Prevention. Advances in global measles control and elimination: summary of the 1997 international meeting. MMWR Recomm Rep. Jul 24 1998;47(RR-11):1-23. [Medline]. [Full Text].
Clements CJ, Cutts FT. The epidemiology of measles: thirty years of vaccination. Curr Top Microbiol Immunol. 1995;191:13-33. [Medline].
Dörig RE, Marcil A, Chopra A, Richardson CD. The human CD46 molecule is a receptor for measles virus (Edmonston strain). Cell. Oct 22 1993;75(2):295-305. [Medline].
Feigen RD, Cherry JD, eds. Prevention of infectious diseases. In: Textbook of Pediatric Infectious Diseases. 4th ed. Philadelphia, Pa: WB Saunders; 1998:2742-44.
Feigen RD, Cherry JD, eds. Measles. In: Textbook of Pediatric Infectious Diseases. Philadelphia, Pa: WB Saunders; 1992:1595.
Griffin DE. Immune responses during measles virus infection. Curr Top Microbiol Immunol. 1995;191:117-34. [Medline].
Habif TP. Exanthems and drug eruptions. In: Clinical Dermatology: A Color Guide to Diagnosis and Therapy. 3rd ed. Philadelphia, Pa: Mosby; 1996:409-12.
Horikami SM, Moyer SA. Structure, transcription, and replication of measles virus. Curr Top Microbiol Immunol. 1995;191:35-50. [Medline].
Katz M. Clinical spectrum of measles. Curr Top Microbiol Immunol. 1995;191:1-12. [Medline].
Madsen KM, Hviid A, Vestergaard M, Schendel D, Wohlfahrt J, Thorsen P, et al. A population-based study of measles, mumps, and rubella vaccination and autism. N Engl J Med. Nov 7 2002;347(19):1477-82. [Medline].
Manchester M, Liszewski MK, Atkinson JP, Oldstone MB. Multiple isoforms of CD46 (membrane cofactor protein) serve as receptors for measles virus. Proc Natl Acad Sci U S A. Mar 15 1994;91(6):2161-5. [Medline].
Naniche D, Varior-Krishnan G, Cervoni F, Wild TF, Rossi B, Rabourdin-Combe C, et al. Human membrane cofactor protein (CD46) acts as a cellular receptor for measles virus. J Virol. Oct 1993;67(10):6025-32. [Medline].
Norrby E. The paradigms of measles vaccinology. Curr Top Microbiol Immunol. 1995;191:167-80. [Medline].
Rima BK, Earle JA, Baczko K, Rota PA, Bellini WJ. Measles virus strain variations. Curr Top Microbiol Immunol. 1995;191:65-83. [Medline].
Smith S. Two more cases of measles are confirmed. Boston Globe. June 15, 2006.
Tatsuo H, Ono N, Tanaka K, Yanagi Y. SLAM (CDw150) is a cellular receptor for measles virus. Nature. Aug 24 2000;406(6798):893-7. [Medline].
rubeola, morbilli, rubeola measles
Melissa Burnett, MD, Attending Physician, Clinical Instructor in Dermatology, Harvard Medical School, Department of Dermatology and Pediatric Dermatology, Cambridge Health Alliance and Massachusetts General Hospital
Melissa Burnett, MD is a member of the following medical societies: American Academy of Dermatology and Massachusetts Medical Society
Disclosure: Nothing to disclose.
Paul Krusinski, MD, Director of Dermatology, Professor, Department of Internal Medicine, Fletcher Allen Health Care, University of Vermont
Paul Krusinski, MD is a member of the following medical societies: American Academy of Dermatology, American College of Physicians, and Society for Investigative Dermatology
Disclosure: Nothing to disclose.
James W Patterson, MD, Director of Dermatopathology, Professor of Pathology and Dermatology, Departments of Pathology and Dermatology, University of Virginia Medical Center
James W Patterson, MD is a member of the following medical societies: American Academy of Dermatology, American College of Physicians, American Medical Association, American Society of Dermatopathology, Medical Society of Virginia, Royal Society of Medicine, Society for Investigative Dermatology, and United States and Canadian Academy of Pathology
Disclosure: Nothing to disclose.
Michael J Wells, MD, Associate Professor, Department of Dermatology, Texas Tech University Health Sciences Center
Michael J Wells, MD is a member of the following medical societies: Alpha Omega Alpha, American Academy of Dermatology, American Medical Association, and Texas Medical Association
Disclosure: Nothing to disclose.
Lester F Libow, MD, Dermatopathologist, South Texas Dermatopathology Laboratory
Lester F Libow, MD is a member of the following medical societies: American Academy of Dermatology, American Society of Dermatopathology, European Academy of Dermatology and Venereology, International Society of Dermatology, Massachusetts Medical Society, New York Academy of Sciences, Phi Beta Kappa, Society for Investigative Dermatology, and Texas Medical Association
Disclosure: Nothing to disclose.
Joel M Gelfand, MD, MSCE, Medical Director, Clinical Studies Unit, Assistant Professor, Department of Dermatology, Associate Scholar, Center for Clinical Epidemiology and Biostatistics, University of Pennsylvania
Joel M Gelfand, MD, MSCE is a member of the following medical societies: Society for Investigative Dermatology
Disclosure: Nothing to disclose.
William D James, MD, Paul R Gross Professor of Dermatology, University of Pennsylvania School of Medicine; Vice-Chair, Program Director, Department of Dermatology, University of Pennsylvania Health System
William D James, MD is a member of the following medical societies: American Academy of Dermatology and Society for Investigative Dermatology
Disclosure: elsevier Royalty Other
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