Other Respiratory Illnesses Going Around

• Common human coronaviruses usually cause mild to moderate upper respiratory tract illnesses, like the common cold. Lower respiratory illnesses, including pneumonia or bronchitis, can also occur. This information applies to common human coronaviruses and should not be confused with the virus that causes COVID-19.
• Seasonality in the US: Coronaviruses spread year-round, with increased activity typically in the fall and winter.
• Who is at higher risk for severe disease? Pneumonia and bronchitis caused by human coronaviruses are more common in people with cardiopulmonary disease, people with weakened immune systems, infants, and older adults.
• How to prevent spread? Practice good hygiene, take steps for cleaner air, and use precautions to prevent spread when you are sick.

Learn more: Common Human Coronaviruses Fact Sheet

Data sources: NREVSS and NVSN post weekly data on these viruses.

• Group A strep is the type of bacteria that causes "strep throat," which can also rarely result in more serious infections like toxic shock syndrome.
• Seasonality in US: Respiratory infections from group A strep can occur year-round but are more common in winter and early spring.
• Who is at higher risk for severe disease? Most infections are minor but serious infections can occur, particularly in older adults and people with certain underlying health conditions.
• What treatments are there? Healthcare providers can test for the presence of group A strep bacteria and treat with antibiotics if needed. In severe cases, surgery may be needed to remove infected tissue or limbs.
• How to prevent spread? Practicing good hand hygiene, covering coughs and sneezes, and taking antibiotics as prescribed, can prevent these bacteria from spreading.

Learn more: About Group A Strep Infection

Data source: Group A Strep Disease Surveillance and Trends

• Human metapneumovirus (HMPV) can cause symptoms including cough, fever, nasal congestion, and shortness of breath. Clinical symptoms of HMPV infection may progress to bronchitis or pneumonia and are similar to other viruses that cause upper and lower respiratory infections.
• Seasonality in the US: HMPV season typically begins in winter and lasts until or though the spring.
• Who is at higher risk for severe disease? Young children, older adults, and people with weakened immune systems are at higher risk for lower respiratory tract infections (bronchitis, bronchiolitis, and pneumonia). HMPV can also exacerbate asthma and chronic obstructive pulmonary disease.
• How to prevent spread? Practice good hygiene, take steps for cleaner air, and use precautions to prevent spread when you are sick.

Learn more: About Human Metapneumovirus

Data sources: NREVSS and NVSN post weekly data on these viruses.

• Mycoplasma pneumoniae is a common cause of mild respiratory illness, although it can also cause a more severe disease known as "walking pneumonia."
• Seasonality in the US: M. pneumoniae infections can occur any time of the year, but they may be more common in summer and early fall.
• Who is at higher risk for severe disease? People of all ages can get sick from M. pneumoniae, but it most commonly affects school-aged children and young adults.
• What treatments are there? Most mild M. pneumoniae infections resolve on their own without medicine, but healthcare providers may treat pneumonia with antibiotics.
• How to prevent spread? CDC recommends following core prevention strategies to prevent respiratory illness, including practicing good hand hygiene and covering coughs and sneezes.

Learn more: About Mycoplasma pneumoniae Infection

Data sources: Mycoplasma pneumoniae Infection Surveillance and Trends

• Most parainfluenza viruses (HPIV) illnesses are mild and typically only require treatment of symptoms. There are four types of human parainfluenza viruses (HPIV-1 through 4), and the symptoms and spread for each HPIV type can sometimes vary. HPIV-1 and HPIV-2 are most often associated with croup (infection of the vocal cords, windpipe, and sometimes into the bronchial tubes). Both can also cause upper and lower respiratory illness. HPIV-3 is more often associated with bronchiolitis (infection in the smallest air passages in the lungs), bronchitis (infection of the main air passages that connect the windpipe to the lungs), and pneumonia. HPIV-4 is recognized less often but may cause mild to severe respiratory illnesses.
• Seasonality in the US: HPIV-1 and HPIV-2 both peak in the fall, often in alternating years. HPIV-3 usually peaks every year in the spring and early summer. HPIV-4 seasonal patterns are not as well defined but appear to occur in fall and winter each year.
• Who is at higher risk for severe disease? HPIVs commonly infect infants, young children, and people with weakened immune systems. However, anyone can get HPIV infection. In children, HPIVs can cause croup, bronchitis, bronchiolitis, and pneumonia. In older adults and people with weakened immune systems, bronchitis and pneumonia may occur.
• How to prevent spread? Practice good hygiene, take steps for cleaner air, and use precautions to prevent spread when you are sick.

Learn more: Clinical Overview of Human Parainfluenza Viruses (HPIVs)

Data sources: NREVSS and NVSN post weekly data on these viruses.

• Pneumococcal disease is the name for any infection caused by Streptococcus pneumoniae bacteria. These infections range from mild (e.g., ear infection, sinus infection) to serious (e.g., pneumonia, meningitis).

• Seasonality in US: Pneumococcal disease is more common during the winter and early spring.

• Who is at higher risk for severe disease? Children younger than 5 years old and adults 65 years and older, people with underlying health conditions, and other risk factors can increase someone's risk for pneumococcal disease.

• What treatments are there? Healthcare providers use antibiotics to treat pneumococcal disease. In severe cases, surgery may be needed to remove infected tissue.

• How to prevent spread? The best way to prevent pneumococcal disease is to get vaccinated. CDC recommends pneumococcal vaccination for all children younger than 5 years old, people 5 through 49 years old with certain risk conditions, and adults 50 years or older.

Learn more: About Pneumococcal Disease

Data sources: Pneumococcal Disease Surveillance and Trends

• Adenoviruses are common and can cause a wide range of signs and symptoms. Respiratory adenovirus infections typically cause mild cold or flu-like symptoms, though they can also cause acute bronchitis, pneumonia, conjunctivitis (pink eye), and acute gastroenteritis (inflammation of the stomach or intestines causing diarrhea, vomiting, nausea, and stomach pain).
• Seasonality in the US: Respiratory adenoviruses spread year-round.
• Who is at higher risk for severe disease? People with weakened immune systems or existing respiratory or cardiac disease are at higher risk of developing severe illness from adenovirus.
• How to prevent spread? Practice good hygiene, take steps for cleaner air, and use precautions to prevent spread when you are sick.

Learn more: Adenovirus

Data sources: NREVSS and NVSN post weekly data on these viruses.

• Rhinoviruses frequently cause the common cold and are a common viral trigger for asthma attacks.
• Seasonality in the US: Rhinoviruses spread year-round but peak typically in the spring and late summer/fall.
• Who is at higher risk for severe disease? RV/EV can cause severe illness if you have a weakened immune system, asthma, or another underlying medical condition. Know the risk factors for severe illness from respiratory viruses.

• How to prevent spread? Practice good hygiene, take steps for cleaner air, and use precautions to prevent spread when you are sick.

Learn more: Rhinovirus & Enterovirus

Data sources: NREVSS and NVSN post weekly data on these viruses.

• Whooping cough is a very contagious respiratory illness caused by a type of bacteria called Bordetella pertussis.
• Seasonality in US: Whooping cough is common throughout the year, with periodic peaks every few years.
• Who is at higher risk for severe disease? People of all ages can get sick with whooping cough but babies younger than 1 year old are at the greatest risk of severe complications.
• What treatments are there? Healthcare providers generally treat whooping cough with antibiotics. Early treatment, before coughing fits begin is important.
• How to prevent spread? CDC recommends whooping cough vaccination for everyone, including pregnant women (which helps protect babies in the early months of life).

Learn more: About Whooping Cough

Data sources: Pertussis Surveillance and Trends

Source: National Syndromic Surveillance Program (NSSP)

• NSSP is a collaboration among CDC, local and state health departments, with private sector partners. Together, these partners collect, share, and analyze automated electronic healthcare data in near-real time.
• National data include emergency departments in all 50 states, the District of Columbia, and Guam. View the coverage map here.

Describing the data:

• Numerators: Emergency department visits with at least one code meeting the condition definition (see table below). A single visit may have multiple codes and may be counted under multiple conditions
• Denominators: All emergency department visits for the selected age group (including respiratory and non-respiratory).
• The conditions below are defined by specific International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM) discharge diagnostic codes included in the CDC Broad Acute Respiratory Index (ARI) Discharge Diagnosis v1 definition.
  • Short codes ending with X include all subcodes with the same three-digit prefix. For example, J06.X includes all subcodes starting with J06 (J06.0 and J06.9) and J21.X includes all subcodes starting with J21 (J21.0, J21.1, J21.8, and J21.9). J06.X includes all subcodes starting with J06.
• The most common conditions for each age group were selected for display on this page by CDC clinicians and subject matter experts. Findings for all 11 conditions are available at data.cdc.gov.

Acute Respiratory Illness (ARI) Condition Descriptions and Code Information