Epidemiology of Rubella Pregnant women are one vulnerable group susceptible to contracting a viral disease. One viral disease that pregnant women can contract is rubella. Rubella is often a mild disease that affects children, adolescents, young adults, and is susceptible to pregnant women. The disease can be devastating when transmitted to the fetus. This paper will discuss the definition and description of epidemiology as well as the steps and methods of epidemiology as it relates to rubella and congenital rubella, by using the epidemiology triangle.
The different types of epidemiology and various levels of prevention for rubella and congenital rubella will be viewed. Epidemiology is a valuable tool concerning nursing and health care. Epidemiology is defined as “the study of the distribution and determinants of health-related states or events in specified populations, and the application of this study to the control of health problems” (Centers for Disease Control, 2006). Epidemiology is important concerning population health management because it examines how health related issues affect a community.
This type of knowledge is used to determine how to lessen exposure to disease throughout the world. Epidemiology is considered the basic science of public health (Stanhope, Lancaster, 2012). Like public health nursing, epidemiology is a complex and continually evolving field with a common focus: the optimal health for all members of all communities, local and global (2012). The practice of epidemiology also can be viewed as a community health problem solving process (The United South and Easter Tribe, Inc. 2009). The epidemiological process parallels the steps in processes familiar to health professions, like the diagnostic process, the nursing process, the scientific process, and the quality improvement process, especially if one sees the target process outcome as improving the health of specified populations vs. an individual (2009). First, there is the problem solving process, and this is by identifying the problem, and the factors involved.
With rubella, the cause is a virus and is spread through the air and through close contact. Congenital rubella occurs when a pregnant woman usually during the first trimester, passes the virus to her developing fetus. Then there is the diagnostic process, which is the symptoms and identifying a possible diagnosis. Postnatal rubella (German measles) is a generally mild, self-limited illness characterized by rash, lymphadenopathy, and low-grade fever (National Center for Biotechnology Information, 1996).
However, congenital rubella may cause a number of anomalies, depending on the organ system involved and gestational age (1996). Using the epidemiological process identifies who is at risk and how to prevent the distribution of the disease. Rubella occurs worldwide with a seasonal distribution (NCBI, 1996). The peak incidence of infection is in late winter or early spring (1996). There have been no major epidemics in the United States since vaccine licensure in 1969, and the incidence has decreased by 99 percent (1996).
Continued cases of congenital rubella are due to infection in unvaccinated, susceptible young women (1996). Rubella can be prevented by routine childhood immunization and by immunization of susceptible adolescents and adult populations with live attenuated rubella vaccine (1996). Immunoglobulin is not very effective in prophylaxis of rubella in pregnant women, and its routine use is not generally recommended (1996). It should be considered only if termination of pregnancy is not acceptable to the mother under any circumstances (1996).
Considering that congenital rubella affects the unborn fetus epidemiologist are concerned about mortality rates. Although measures of mortality reflect serious health problems and changing patterns of disease, they are limited in their usefulness (Stanhope, Lancaster, 2012). Mortality rates are informative only for fatal diseases and do not provide direct information about either the level of existing disease in the population or the risk of contracting any particular disease (2012).
Since a vaccine has been the process to help with the spread of rubella, it is important to educate the public the importance of being vaccinated (2012). One of the benefits of epidemiological studies is that the results may demonstrate which disease prevention and control interventions are more useful and effective (Stanhope & Lancaster, 2008). When doing an epidemiological study it is done with a descriptive and analytical evaluation, to determine the causes and factors that actuate incidence of disease and other health related activity.
When using analytical studies the researcher will use studies that provide “why” and “how” a disease affects a community. Characterizing health events by time, place, and person are activities of descriptive epidemiology, discussed in more detail later in this lesson (CDC, 2006). Studies have been done using both analytical and descriptive for Rubella and Congenital Rubella. During the period of 1964 and 1964, there was an epidemic outbreak of rubella, also known as German measles worldwide.
Pregnant women who contracted rubella in the first trimester of their pregnancy could pass the rubella virus to their developing fetus, causing the child to be born deaf, blind, with cardiac problems, developmental delays and other medical conditions (Helen Keller National Center, 2008). In the United States alone, approximately 20,000 children were born during this epidemic with two or more of these symptoms (2008). This constellation of symptoms is known as congenital rubella syndrome, or CRS (2008). Rubella occurs worldwide (CDC, 2006).
There have been no major epidemics in the United States since the licensure of the live attenuated rubella vaccine in 1969 (2006). However, limited sporadic outbreaks of rubella continue to occur each year, particularly in settings (such as schools) where susceptible individuals come into close contact (2006). The incidence of infection shows the same prominent seasonal pattern as for other respiratory diseases (2006). Epidemiological triangle can be used to comprehend how rubella and CRS are contracted and transmitted.
There are three elements that cause this virus, an external agent, a susceptible host, and an environment that bring the host and agent together. Rubella is the infectious virus (CDC, 2006). Rubella virus is a spherical, 40- to 80-nm, positive-sense, single-stranded RNA virus with spike-like, hemagglutinin-containing surface projections (2006). An electron-dense 30 to 35 nm core is surrounded by a lipoprotein envelope (2006). In the epidemiological triangle, the host can be anything that harbors infection; this is usually a human or an animal.
The ecologic model spans a broader spectrum of systems and etiological factors than the more traditional web of causality model and it encompasses determinants at many levels: biological, mental, behavioral, social, and environmental factors, including policy, culture, and economic environments (Stanhope, Lancaster, 2008). The disease is transmitted via direct or droplet contact with respiratory secretions (CDC, 2006). Rubella virus multiplies in cells of the respiratory system; this is followed by viremic spread to target organs (2006).
Congenital infection is transmitted transplacentally (2006). Humans are the only known reservoir of rubella virus, with postnatal person-to-person transmission occurring via direct or droplet contact with the respiratory secretions of infected persons (2006). Although the early events surrounding infection are incompletely characterized, the virus almost certainly multiplies in cells of the respiratory tract, extends to local lymph nodes, and then undergoes viremic spread to target organs (2006). The incubation period is approximately fourteen days.
For pregnant women the first three to four months of pregnancy are the most vulnerable to transmit the virus to the fetus. Studies show that the virus produces chromosomal abnormalities. Rubella infection acquired during pregnancy can result in stillbirth, spontaneous abortion, or several anomalies associated with the congenital rubella syndrome (2006). The clinical features of congenital rubella vary and depend on the organ system(s) involved and the gestational age at the time of maternal infection (2006).
The classic triad of congenital rubella syndrome includes cataracts, heart defects, and deafness, although many other abnormalities (2006). These symptoms can be either temporary or permanent and can be alone or in combination. Rubella is definitely a public health concern and all levels of prevention (primary, secondary, and tertiary) should be educated to the public. Primary prevention relates to interventions to prevent the occurrence of disease. This first level of prevention includes broad efforts such as health promotion, environmental protection, and specific protection (Stanhope, Lancaster, 2008).
Since 1969, several live attenuated rubella vaccines for the prevention of rubella have been licensed for use in the United States (CDC, 2008). The vaccine in current use is prepared from attenuated rubella virus (RA 27/3) and induces immunity by producing a modified rubella infection in susceptible recipients (2008). The immunization strategy in the United States is aimed at minimizing the potential for exposure of pregnant women (and through them, their fetuses) to rubella by using vaccination programs designed primarily to provide widespread childhood immunity to rubella and to reduce the occurrence of disease in the community (2008).
Secondary prevention relates to interventions that a person with an illness will have it diagnosis at a time that it can be treated, and a probability of curing the diagnosis. Having a yearly examine is an intervention for secondary prevention. Patients with postnatal rubella should be excluded from childcare, school, or the workplace for 7 days after the onset of rash (Best Practice, 2011). Droplet and standard precautions are recommended for hospitalized patients (BP, 2011).
Contact isolation is recommended for congenitally infected infants until 2 serial nasopharyngeal and urine cultures obtained after 3 months of age are sterile, or for the first year of life (2011). Post-pubertal women should be assessed for susceptibility to rubella at all healthcare encounters (2011). If these women are found to be susceptible by serological screening or their immunization status is undocumented, they should be immunized with measles-mumps-rubella (MMR) vaccine unless they are known to be pregnant (2011). Routine prenatal screening for rubella immunity is recommended (2011).
If the patient is susceptible, MMR should be given in the immediate postpartum period (2011). People at increased risk of rubella infection (healthcare professionals, educators, childcare workers) should be assessed for susceptibility to rubella and, if susceptible, should be immunized with MMR vaccine (2011). Tertiary prevention relates to maintaining the disease through rehabilitation by educating patients on compliance of medications to help with the treatment of disease. Medical treatment, physical and occupational therapy, and rehabilitation are intervention characterized as tertiary prevention (Stanhope, Lancaster, 2012).
Children born with congenital rubella are often deaf, blind, and have mental retardation. Education provided to the parents is a necessity, such as having early hearing screenings, keeping up with annual physicals, and keeping appoints with the necessary therapist that provides care to these patients. Even though vaccinations are available for prevention of rubella, there is still an epidemic in other countries. At the National Immunization Conference in 2005, it was announced that rubella was no longer an epidemic in the United States.
Rubella remains endemic in parts of the world; in 2008 WHO estimated 110,000 cases of CRS worldwide, many of them in Asia and Africa (Stanhope, Lancaster, 2012). In 2008, WHO also reported 123 countries, or about two thirds of countries, regularly using rubella in their national immunization programs, with the highest coverage in the Americas and Western Europe (2012). Immigrants are still entering the United States this makes it more important to continue to educate the public about vaccinations and keeping current with childhood vaccinations.
Other countries need to consider the important of preventing the spread of disease even though the cost of immunizations could be expensive. Epidemiology has made outstanding advancement in healthcare since it began. It is important to continue to advance in this field to maintain the health of the public and to help fight disease. Through epidemiology rubella and congenital rubella has decreased from education provided by public health to communities across the globe. Through descriptive and analytical approaches, epidemiologists have been able to narrow the scope on the advancement in the study of rubella and congenital rubella.
Epidemiologists have been able to use the epidemiology triangle to help demonstrate the distinction between agent, host, and the environment with rubella infections. Using primary, secondary, and tertiary prevention will help to reduce the spread of the rubella virus globally and increase the chance of newborns not being born with congenital rubella. Large-scale rubella vaccination during the last decade has drastically reduced or practically eliminated rubella and CRS in many developed and in some developing countries (World Health Organization, 2012).
