DENVER Three new cases of the highly contagious measles virus have been confirmed in two Colorado counties this week, bringing the state total to 36 so far this year, state health officials said Monday.The first case the first for Weld County this year was confirmed in an unvaccinated school-aged child who developed symptoms after traveling out-of-state to an area where there is an ongoing measles outbreak. The other two cases, also unvaccinated, were identified as household contacts of a previously confirmed case in Montezuma County.No known public exposures were identified in connection with these three newest cases, a spokesperson with the Colorado Department of Public Health and Environment (CDPHE) told Denver7 in an email.With the holiday season in full swing, getting vaccinated is the best way to protect yourself, your family, and your community from measles, said Dr. Rachel Herlihy, the CDPHEs epidemiologist and deputy chief medical officer.She added vaccination is critical to protect infants too young to be vaccinated and family members with weakened immune systems.How to spot a potential measles infectionWhile there were no known public exposures connected to these latest cases, people who believe they may have measles especially those who have not been vaccinated with the MMR vaccine should monitor for symptoms for 21 days and avoid public gatherings or high-risk settings, health officials said in a news release.Symptoms to watch out for include anything from a fever, a cough, a runny nose, and red, watery eyes that develop into a rash that starts on the face and then spreads to the rest of the body about three to five days after symptoms first start. A person with measles is contagious four days before and four days after the rash appears.While most people recover within two or three weeks after contracting the virus, unvaccinated people run the risk of complications from the disease, including ear infections, seizures, pneumonia, immune amnesia, brain damage and ultimately, death.Measles only spreads from people who show symptoms; it does not spread from people who arent feeling sick, state health officials said. Denver7 has been closely following confirmed cases of measles in Colorado amid a multi-state outbreak of the virus in the U.S. this year. Explore the timeline map below to see more on where cases have so far popped up:Unvaccinated people exposed to the virus can get the MMR vaccine 72 hours after exposure (but before symptoms are present) to prevent an infection, according to health officials. Immunoglobulin (IG), if administered within six days of exposure, may also be used in some circumstances, they added.While the two-dose series of the MMR vaccine has a 97% efficacy rate against infection, about 3 in every 100 people can still get infected if exposed to the virus, according to the U.S. Centers for Disease Control and Prevention (CDC). Vaccinated individuals will usually develop milder symptoms and are less likely to spread it to others, according to state health officials.People who got vaccinated against measles before 1968 should talk to their health care provider about possibly getting a booster as the vaccine used before that year wasn't as effective.Colorado experiencing worst measles outbreak in 30 yearsThese latest cases bring Colorado's tally to 36 so far this year amid a multi-state outbreak across the country.The last time Colorado saw this many cases of the virus was in 1995, when the state reported 26 for the whole year to the CDC. On average, Colorado sees between zero and two cases each year.As of Dec. 15, Colorado has confirmed cases of the virus in Adams (4), Arapahoe (5), Archuleta (1), Boulder (1), Denver (4), El Paso (4), Mesa (11), Montezuma (4), Pueblo (1), and Weld (1) counties. Most have been in unvaccinated individuals. ...read more read less