Strep throat occurs because of an infection from Group A streptococcus (GAS) bacteria. The said infection invades the pharyngeal tissue, leading to a localized inflammatory reaction in the throat and tonsils.1
Group A streptococcus bacteria responsible for strep throat are usually found in the throat or on the skin. This should not be confused with another type of strep bacteria, aptly named Group B, that resides in the digestive system and the vagina.2
Harmful Effects of These Types of Bacteria
Take note that both types of streptococcus bacteria are dangerous. Group A usually leads to different diseases such as impetigo, cellulitis, sinusitis, scarlet fever, sepsis, meningitis, pneumonia, necrotizing fasciitis, and streptococcal toxic shock syndrome.3,4
Meanwhile, Group B is associated with negative effects on pregnant women and newborn babies. This is because the bacteria can be passed by the mother to her child via the amniotic fluid or in the birth canal where the baby passes during labor.
Group B bacteria can also result in miscarriage or stillbirth, although cases like these are rare.5
Newborn babies are then prone to develop infections like meningitis and pneumonia because their immune systems aren't fully developed yet. Within the first few hours or days after they're born, infected newborns are most likely to:6
- Be floppy, unresponsive, and irritable
- Grunt when breathing
- Have poor feeding
- Have unusually high or low temperature, breathing frequencies, and/or slow heart rate
New mothers should also watch out for fevers, vomiting, and reduced consciousness in their babies.7
Common Risk Factors for Strep Throat
Other important facts you should know about strep throat are the risk factors involved. There are two known risk factors that affect your chances of being diagnosed with strep throat: your age and the time of the year.
Strep throat mainly affects school-aged children and teenagers between 5 to 15 years old. It's reported that an estimated 15 to 40 percent of sore throat cases among this age group is caused by the streptococcus bacteria. But remember that even adults can be diagnosed with strep throat, although the incidence is lower (at 5 to 10 percent sore throat cases) compared to children.
The time of the year also plays a role in the onset of strep throat. The bacterial infection is contagious and can be transferred from one person to another through close contact with saliva or nasal secretions from an infected person, usually in the form of airborne respiratory droplets.8
As a result, most cases of strep throat occur between late fall and early spring. Places like schools and daycare centers are open during these periods, paving the way for contact among people there and a higher risk for strep throat.
Scientists are currently analyzing a possible link between a strep infection and a condition that is commonly occurring in children, called pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections, or simply PANDAS.9,10 A child may be diagnosed with PANDAS if he or she experiences a sudden appearance of obsessive compulsive disorder (OCD) and/or tic disorders, or a worsening of OCD or tic symptoms after a strep infection.11