How long is strep throat contagious?

Without treatment, strep throat can be contagious for two to three weeks. After starting antibiotics, a person is generally no longer contagious after 24 hours of treatment.

Can you have strep throat without a fever?

While fever is a common symptom, it is possible to have strep throat without a significant fever. A rapid strep test or throat culture can confirm the diagnosis regardless of symptoms.

Why is it important to complete the full course of antibiotics?

Completing the full 10-day antibiotic course ensures all bacteria are eliminated, even if symptoms improve sooner. Stopping early increases the risk of complications like rheumatic fever and promotes antibiotic resistance.

InfectiousICD-10: J02.0Causes 5-15% of sore throat visits in adults and 20-30% in children

Strep Throat

Also known as: Streptococcal pharyngitis, Group A strep pharyngitis

Strep throat is a bacterial infection of the throat and tonsils caused by group A Streptococcus bacteria. It causes a sudden, severe sore throat with pain when swallowing, fever, and swollen lymph nodes. Unlike viral sore throats, strep throat requires antibiotic treatment to prevent serious complications such as rheumatic fever.

At a Glance

Common symptoms: Sudden severe sore throat, Pain when swallowing, Fever of 101°F (38.3°C) or higher
Main treatments: Antibiotics such as penicillin or amoxicillin for 10 days, Over-the-counter pain relievers for throat pain and fever, Rest and adequate fluid intake
Category: Infectious · Causes 5-15% of sore throat visits in adults and 20-30% in children
See a doctor if: Sore throat accompanied by fever

Symptoms

Sudden severe sore throat

Pain when swallowing

Fever of 101°F (38.3°C) or higher

Red and swollen tonsils, sometimes with white patches or streaks of pus

Tiny red spots on the roof of the mouth

Swollen, tender lymph nodes in the neck

Headache

Body aches

Nausea or vomiting, especially in children

Causes

Infection with group A Streptococcus bacteria
Spread through respiratory droplets when an infected person coughs or sneezes
Touching contaminated surfaces and then touching the mouth or nose

Risk Factors

Age between 5 and 15 years
Close contact with someone who has strep throat
Time of year, with fall and winter being peak seasons
Crowded settings such as schools and daycare

Diagnosis

Rapid antigen detection test from throat swab
Throat culture for definitive diagnosis
Physical examination of the throat and lymph nodes

Treatment

Antibiotics such as penicillin or amoxicillin for 10 days
Over-the-counter pain relievers for throat pain and fever
Rest and adequate fluid intake
Warm salt water gargles
Throat lozenges for symptom relief

Prevention

Frequent handwashing
Avoiding sharing cups, utensils, or food with infected individuals
Replacing toothbrush after starting antibiotics
Staying home until fever-free and on antibiotics for at least 24 hours

When to See a Doctor

Sore throat accompanied by fever
Difficulty swallowing or breathing
Sore throat that lasts longer than 48 hours
Rash accompanying a sore throat

Frequently Asked Questions

Related Conditions

Tonsillitis

Infectious

Scarlet Fever

Infectious

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