A Guide to Outbreak Investigation

Welcome to this video on

outbreak

investigation

, we will see what an

outbreak

is, how it is detected, investigated and controlled, first of all, what is an outbreak, basically an outbreak is when there are more cases of disease than normally expected in a population in a given area and at a given time, the terms epidemic and outbreak are sometimes used interchangeably. How do we detect outbreaks well? There are several different ways to know about an outbreak through a variety of surveillance methods, including passive surveillance, which is routine monitoring. collected health data active surveillance when health information is actively sought Sentinel surveillance where health data is provided by selected groups or institutions syndromic surveillance which is the monitoring of disease syndromes or through a variety of other sources of information, including news from social media or even rumors once a year A decision is made to investigate the outbreak.

Go through a few systematic steps. The number of steps, order and content may vary and multiple steps may be performed at the same time, but in essence, an outbreak

investigation

consists of confirming whether there is an outbreak, describing it and determining. the cause of the outbreak and then implement control measures so that it does not spread further or occur again. Let's look at the steps in a little more detail. Confirming that there is an outbreak is the first step of an outbreak investigation to determine if there are more cases of illness than expected, we need to know the initial level of illness in that population for that given time, then we can compare it to the level of illness that We are watching to see if there is an increase, however, it is important to note that even if there are more cases than expected, it is necessary to rule out other causes of this apparent increase, such as a sudden increase in laboratory tests or an error of diagnosis or a sudden increase in population, to determine what is causing the outbreak and help decide.

Regarding the best control method, it is necessary to verify the diagnosis, this is usually done by reviewing the clinical and laboratory findings. Now, at this stage, immediate action may already be taken to control the outbreak, especially if the source and mode of transmission are known. To continue investigating the outbreak, it may be necessary to assemble a team. The size of the team will depend on the nature of the outbreak. Once the outbreak has been confirmed, the next step is to describe the outbreak. Describing the outbreak provides insight into who is affected, where the disease occurs, and other characteristics of the outbreak, let's take a closer look at describing the outbreak.

Investigators must determine who should be considered a case, determine if all cases have been found, and then describe the cases to determine who should be considered. considered as a case, there needs to be a case definition that establishes the criteria that must be met to classify a person as the case, generally there are criteria of time, place, clinical and laboratory characteristics of the person that must be met before that a person can be classified as a case once there is a case definition cases are searched systematically and information about the cases is recorded this is usually done through questionnaires and summarized by time person and place let's take a look at each of them because each of these provides useful information about the outbreak by describing the occurrence of cases over time.

Researchers can look at how the disease has developed over time. This is usually shown on a graph showing the number of cases on the y-axis and time on the x-axis this type of graph is known as an epidemic curve there are two common patterns of an epidemic curve the first is a point source outbreak this happens when the outbreak comes from a point source, for example, if there is an outbreak of gastroenteritis after eating a contaminated dish served in a restaurant the typical pattern is a sharp increase in cases followed by a rapid decrease the other is a spread outbreak this pattern is common in outbreaks where the infection is transmitted from person to person and the first wave of infections is a source for the next wave the typical pattern of this curve is a series of progressive peaks of disease the other descriptor is location this can provide information about the geographic spread of the disease and identify whether there are clusters Modern cartographic and geographic tools Information systems technology have become important tools for mapping and tracking outbreaks.

Describing people affected by the outbreak, for example by age, sex, occupation and ethnicity, can provide useful information about the disease. It allows researchers to determine who is most at risk. In the second step of an outbreak investigation, which is how to describe an outbreak, finding out what caused the outbreak is the next part of the outbreak investigation from the information available in the steps before investigators can have an explanation. of the probable cause of an outbreak. This is also known as hypothesis now, if the pathogen that is the cause of the outbreak is already known then it can provide useful information to

guide

researchers towards the likely source and mode of transmission, for example in an outbreak caused by cholera. , researchers would analyze the contaminated cases. water as a potential source of the outbreak, if it is a salmonella outbreak, it is likely due to contaminated eggs or meat products;

However, it is not very clear, researchers must test and confirm the hypothesis that was developed, this is usually done with an analytical epidemiological study, the two The most commonly used types of analytical studies and outbreak investigations are cohort studies and Case-control studies. These studies can determine the probability that a certain factor is the cause of an outbreak. In addition to analytical epidemiological studies, an environmental investigation can also help confirm the hypothesis, for example, in a foodborne outbreak, mental investigation could identify factors such as contaminated eggs, inadequate food storage or poor hygiene standards that may have been present. contributed to or caused the outbreak.

Laboratories are very useful as they can provide microbiological information to confirm the hypothesis and that concludes our third step in determining what may have caused the outbreak. Now let's discuss the main goal of investigating an outbreak. Control can occur at any stage of the outbreak investigation and can target any step in the transmission pathways between the host agent and the control environment. Measures include behavioral interventions such as using mosquito repellents to prevent mosquito-borne diseases vaccines such as administering the measles vaccine during a measles outbreak medications such as ivermectin for scabies outbreaks environmental measures such as insecticide spraying during an outbreak of malaria or improving water quality during a cholera outbreak infection control measures such as isolating infectious cases using appropriate personal protective equipment and disinfecting medical equipment to restrict further spread of infection by providing appropriate and specific health education will ensure that those who are sick know what to do to stop the spread of the disease and those who are not sick will know what to do to avoid getting sick after control measures are implemented, there must be active surveillance to monitor the outbreak and ensure that control measures are working.

It was a quick look at the different ways an outbreak can be controlled. Now let's talk. About communication, this is an important aspect of managing any outbreak, whether large or small, communication is about ensuring that accurate and timely information reaches the right people at the right time, these may be those internal to the organization or external to the organization. Like other organizations and the public, communicating with the public is important, especially for those affected by the outbreak, it allows them to adopt protective behaviors, helps with disease surveillance and reduces anxiety, confusion and misinformation, the media Communication can be a useful partner and an excellent communication exchange. information about the outbreak using online forums or scientific journals and describing what measures were taken that were effective and what lessons were learned can help others manage future outbreaks;

Finally, once researchers are satisfied that the outbreak is under control, it should be declared over for infectious diseases. This usually occurs when there are no cases after two incubation periods have passed and that is a quick look at infectious disease outbreaks. We take a look at what they are, how they are detected, and the steps involved in an outbreak investigation, including ways outbreaks are controlled.