Hantavirus Cardiopulmonary Syndrome (HCPS) is a rare, but often fatal, disease of the lungs. Although many hantaviruses exist in nature, HCPS in the western U.S. is caused by a specific virus called Sin Nombre. Cases of HCPS occur throughout the U.S., but are most common in the Southwest. The hantavirus is passed to humans from wild rodents. In California, only deer mice carry and shed the virus. Other rodents such as squirrels, chipmunks, and house mice are rarely, if ever, infected and do not pose a risk of HCPS to humans. Infected rodents shed hantavirus in their urine, droppings, and saliva. Most people become infected by breathing air contaminated with rodent urine or droppings, such as when cleaning out a rodent-infested space. This most commonly occurs in small, confined spaces where there is little air circulation. In rare cases, people can also be infected by eating food contaminated with rodent urine or droppings, touching surfaces where rodents have been and then putting their hand in their mouth, or being bitten by an infected rodent. Symptoms occur one to two weeks after being exposed to the Sin Nombre virus and include fever, headache, and muscle aches, especially the thighs, hips, back, and shoulders. Other early symptoms include dizziness, chills, nausea, vomiting, diarrhea, and abdominal pain. After two to seven days of these symptoms, patients develop breathing difficulties that range from cough and shortness of breath to severe respiratory failure. About 40 percent of those with HCPS die from the disease. HCPS is diagnosed through a blood test and there is no specific treatment for the disease.
Hepatitis A is a contagious liver disease that is caused by the Hepatitis A virus. The best way to prevent Hepatitis A is to get vaccinated. People get Hepatitis A by consuming food or drinks that have been contaminated with fecal matter from an infected person, or touching objects that have come in contact with infected fecal matter and then touching the eyes, nose, or mouth. Even the tiniest amount can cause illness. Hepatitis can be spread when an infected person does not wash his or her hands properly after going to the bathroom, a caregiver does not properly wash his or hands after changing a diaper or cleaning up the stool of an infected person, or by engaging in certain sexual activities with an infected person, such as oral-anal contact. Symptoms include fever, fatigue, loss of appetite, nausea, vomiting, abdominal pain, grey-colored stools, dark urine, joint pain, and jaundice (yellowing of the skin). Hepatitis A can be diagnosed with a blood test. Most people who get Hepatitis A feel sick for several months, but usually recover completely and do not have long-term liver damage. In rare cases, Hepatitis A can cause liver failure and even death, mostly in people over age 50 and those with other liver diseases. Hepatitis A is treated with rest, adequate nutrition, fluids, and medical monitoring. Some people will need to be hospitalized.
Hepatitis B is a contagious liver disease that is caused by the Hepatitis B virus. The best way to prevent Hepatitis B is to get vaccinated. The virus is transmitted through blood, semen, and other body fluids from an infected person. People get Hepatitis B through unprotected sex or by using needles or syringes used by someone with Hepatitis B. It can also be passed from an infected mother to her baby at birth. When first infected, a person can develop an acute infection, which can range in severity from very mild with no or few symptoms to a serious condition requiring hospitalization. Acute Hepatitis B refers to the first six months after someone is exposed to the virus. Some people are able to fight the infection and for others, the infection remains, leading to a chronic or lifelong illness. Most adults have symptoms that appear within three months of exposure. Symptoms can last from weeks to several months and include fever, fatigue, loss of appetite, nausea, vomiting, abdominal pain, grey-colored stools, dark urine, joint pain, and jaundice (yellowing of the skin). Hepatitis B can be diagnosed with a blood test. Acute Hepatitis B is treated with rest, adequate nutrition, fluids, and medical monitoring. Those living with chronic Hepatitis B should be evaluated for liver damaged and monitored on a regular basis.
Leptospirosis is an infection caused by a type of Leptospira bacteria. It can infect both humans and animals. The bacteria usually enter the body through broken skin or the mucous membranes (nose, mouth, eyes) with water contaminated by the urine of infected domestic or wild animals or people. People can also become infected by touching the urine or tissues of infected animals and touching their nose, mouth, or eyes. Sickness can occur from two days to four weeks after exposure. Symptoms include fever, headache, chills, red eyes, and sore muscles. Severe infections can result in anemia, jaundice, liver failure, kidney failure, meningitis, and respiratory distress. Leptospirosis can be treated with antibiotics.
Listeriosis is a serious infection caused by Listeria monocytogenes bacteria. The bacteria are commonly found in soil and water and on plant material. Listeria has also been found in raw foods, such as uncooked meats and vegetables, as well as in foods that become contaminated after processing, such as soft cheeses and cold cuts at the deli counter. In addition, unpasteurized (raw) milk and foods made from unpasteurized milk may contain the bacteria. Listeriosis can cause severe illness in newborns, pregnant women, the elderly, and anyone with a weakened immune system. Illness can range from fever and diarrhea to infections resulting in brain damage or death. Healthy adults and children who are infected with the bacteria rarely become seriously ill.
Malaria is a mosquito-borne disease caused by parasites called Plasmodium that infect and destroy red blood cells. There are four types of Plasmodium. Malaria occurs in many tropical and sub-tropical areas of the world. Nearly all cases in the United States are in people who traveled to areas where malaria is more common. People get malaria from the bite of an infected mosquito. A mosquito can become infected when it bites a person who has malaria organisms in the blood. It takes a week or more for the malaria organisms to mature in the mosquito; then the mosquito can transmit the organism to another person when it bites them. Symptoms usually occur one to four weeks after being infected, though in some cases symptoms do not appear for up to a year. Fever is the most common early symptom of malaria. The fever tends to rise over several days and may be accompanied by headache, muscle pain, and fatigue. Temperatures of 104° to 106°F may be reached and patients may experience intense shaking chills and sweating. These symptoms occur repeatedly for several hours every one to three days. Infection with the Plasmodium falciparum parasite can progress to severe symptoms, coma, and death. Malaria can be cured with medicine. The type of drugs and length of treatment depend on which kind of malaria is diagnosed, where the patient was infected, the age of the patient, and how severely ill the patient was at the start of treatment. Some forms of malaria from South America and Southeast Asia are less susceptible to standard malaria drugs.
Measles, Mumps, Rubella
Measles is a highly contagious disease caused by a virus. It begins with a fever that lasts for a couple of days, followed by a cough, runny nose, and conjunctivitis (pink eye). Infected people are usually contagious from a few days before their rash starts to four days afterward. Mumps is a contagious disease that is caused by the mumps virus. Mumps typically starts with a few days of fever, headache, muscle aches, tiredness, and loss of appetite, followed by swelling of the glands that produce saliva. Rubella is a respiratory disease caused by a virus. It is spread by sneezing and coughing. Common symptoms include rash and fever for two to three days. When a woman is infected with rubella during pregnancy, complications for the infant may include deafness, cataracts, heart defects, mental retardation, and liver and spleen damage. Most infants born in the United States receive passive protection against measles, mumps, and rubella in the form of antibodies from their mothers. These antibodies can destroy the vaccine virus if they are present when the vaccine is administered and cause it to be ineffective. By 12 months of age, almost all infants have lost this passive protection. Children should get their first dose of the MMR (measles, mumps, rubella) vaccine at age 12 months or later. The second dose of MMR is usually administered before the child begins kindergarten, but may be given one month or more after the first dose.
Meningococcal disease refers to meningitis, an inflammation of the membranes that cover the brain and spinal cord. People sometimes call it spinal meningitis. It is usually caused by a viral or bacterial infection. Knowing whether meningitis is caused by a virus or bacterium is important because the severity of illness and the treatment differ depending on the cause. Viral meningitis is generally less severe and clears up without specific treatment. But bacterial meningitis can be quite severe and may result in brain damage, hearing loss, or learning disabilities. The best way to protect against bacterial meningitis is by getting vaccinated. Some forms of bacterial meningitis are contagious. The bacteria can mainly be spread from person to person through the exchange of respiratory and throat secretions. This can occur through coughing, kissing, and sneezing. Fortunately, none of the bacteria that cause meningitis are spread by casual contact or by simply breathing the air where a person with meningitis has been. Symptoms can develop over several hours or they can take one to two days and include high fever, headache, and stiff neck. Other symptoms may include nausea, vomiting, discomfort looking into bright lights, confusion, and sleepiness. In newborns and small infants, the classic symptoms of fever, headache, and neck stiffness may be absent or difficult to detect. Infants with meningitis may appear slow or inactive, have vomiting, be irritable, or be feeding poorly. As the disease progresses, patients of any age may have seizures. Early diagnosis and treatment are very important. If symptoms occur, see a doctor immediately. The diagnosis is usually made by growing bacteria from a sample of spinal fluid. The spinal fluid is obtained by performing a spinal tap, in which a needle is inserted into an area in the lower back where fluid in the spinal canal can be collected. If the meningitis is bacterial, identifying the type of bacteria responsible is important for selecting the correct antibiotic to use. Bacterial meningitis can be treated with a number of effective antibiotics.