Disease | Mode of Spread | Symptoms | Incubation Period | Contagious Period | Contacts | Exclusions (subject to LHD approval) |
Adenovirus | Droplet; contact with respiratory secretions, contaminated surfaces, or stool | Fever, cough, runny nose, sore throat, bronchitis, pneumonia, conjunctivitis, vomiting, diarrhea | Respiratory: 2-14 days Intestinal: 3-10 days | Most contagious during the first few days of symptoms; can be shed for weeks | Exclude with first signs of illness; encourage good hand hygiene | Exclude until 24hr with no fever and symptoms improving |
Campylobacteriosisⱡ | Ingesting raw milk, undercooked meat, contaminated food / water; animal contact | Diarrhea (may be bloody), abdominal pain, malaise, fever | Average 2-5 days (range 1-10 days) | Throughout illness (usually 1-2 weeks, but up to 7 weeks without treatment) | Exclude with first signs of illness; encourage good hand hygiene | Exclude until diarrhea has ceased for at least 2 days; additional restrictions may apply |
Chickenpox** ⱡ (Varicella) 
| Person-to-person by direct contact, droplet or airborne spread of vesicle fluid, or respiratory secretions | Fever, mild respiratory symptoms, body rash of itchy, blister-like lesions, usually concentrated on the face, scalp, trunk | Average 14-16 days (range 10-21 days) | As long as 5 days, but usually 1-2 days before onset of rash and until all lesions have crusted | Exclude contacts lacking documentation of immunity until 21 days after last case onset | Until lesions crusted and no new lesions for 24hr (for non-crusting lesions: until lesions are fading and no new lesions appear) |
CMV (Cytomegalovirus) | Exposure to infectious tissues, secretions, or excretions | None or “mono-like” | 1 month | Virus may be shed for 6 months to 2 years | If pregnant, consult OB; contacts should not be excluded | No exclusion necessary |
Common Cold | Person-to-person; droplet or airborne respiratory secretions; contaminated surfaces | Runny or stuffy nose, slight fever, watery eyes | Variable, usually 1-3 days | 24hrs before onset to up to 5 days after onset | Encourage cough etiquette and good hand hygiene | Exclude until 24hr with no fever and symptoms improving |
COVID-19ⱡ 
| Airborne or contact with respiratory secretions; person-to- person or by touching contaminated surfaces | Fever, sore throat, shortness of breath, difficulty breathing, cough, runny nose, congestion, fatigue, vomiting, diarrhea | Average 5 days (Range 2-14 days) | 2 days prior to symptom onset and potentially after symptom resolution | Mask and monitor health for 10 days; test 5 days after exposure and if symptoms develop; avoid unmasked activities | Exclude until 24hr with no fever and symptoms have improved and 5 days since onset (positive test if no symptoms) |
Croup | Airborne or contact with respiratory secretions | Barking cough, difficulty breathing | Variable based on causative organism | Variable based on causative organism | Encourage cough etiquette and good hand hygiene | Exclude until 24h with no fever and symptoms improving |
Diarrheal Illness (Unspecified) | Fecal-oral: person-to- person, ingesting contaminated food or liquid, animal contact | Loose stools, nausea, vomiting, abdominal cramps, fever possible | Variable based on causative organism | Variable based on causative organism | Exclude with first signs of illness; encourage good hand hygiene | Exclude until diarrhea has ceased for 24h or until medically cleared |
Disease | Mode of Spread | Symptoms | Incubation Period | Contagious Period | Contacts | Exclusions (subject to LHD approval) |
E. coli ⱡ (Shiga toxin- producing) | Fecal-oral: person-to- person, from contaminated food or liquid, animal contact | Abdominal cramps, diarrhea (may be bloody), gas, nausea, fever, or vomiting | Variable, usually 2-10 days | For duration of diarrhea until stool culture is negative | Exclude with first signs of illness; encourage good hand hygiene | Medical clearance required; Exclude until diarrhea has ceased for at least 2 days |
Fifth Disease (Erythema infectiosum) (Parvovirus B19) | Person-to-person; Contact with respiratory secretions | Fever, flushed, lacy rash (“slapped cheek”) | Variable, usually 4- 20 days | Most infectious before 1-2 days prior to onset | If pregnant, consult OB; encourage good hand hygiene; do not share eating utensils | No exclusion if rash is diagnosed as Fifth disease by a healthcare provider |
Giardiasis** ⱡ | Person-to-person transmission of cysts from infected feces; contaminated water | Diarrhea, abdominal cramps, bloating, fatigue, weight loss, pale, greasy stools; may be asymptomatic | Average 7-10 days (range 3-25+ days) | During active infection | Encourage good hand hygiene | Exclude until diarrhea has ceased for at least 2 days; may be relapsing; additional restrictions may apply |
Hand Foot and Mouth Disease** (Coxsackievirus) (Herpangina) | Contact with respiratory secretions or feces from an infected person | Sudden onset of fever, sore throat, cough, tiny blisters in mouth/throat and on extremities | Average 3-5 days (range 2-14 days) | From 2-3 days before onset and several days after onset; shed in feces for weeks | Exclude with first signs of illness; encourage cough etiquette and good hand hygiene | If secretions from blisters can be contained, no exclusion required |
Head lice (Pediculosis) | Head-to-head contact with an infected person and/or their personal items such as clothing or bedding Head Lice Manual | Itching, especially nape of neck and behind ears; scalp can be pink and dry; patches may be rough and flake off | 1-2 weeks | Until lice and viable eggs are destroyed, which generally requires 1-2 shampoo treatments and nit combing | Avoid head-to-head contact during play; do not share personal items, such as hats, combs; inspect close contacts frequently | Students with live lice may stay in school until end of day; immediate treatment at home is advised |
Hepatitis A** ⱡ 
| Fecal-oral; person-to- person or via contaminated food or water | Loss of appetite, nausea, fever, jaundice, abdominal discomfort, diarrhea, dark urine, fatigue | Average 25-30 days (range 15-50 days) | 2 weeks before onset of symptoms to 1 to 2 weeks after onset | Immediately notify LHD regarding evaluation and treatment of close contacts; encourage good hand hygiene | Exclude until 7 days after jaundice onset and medically cleared; exclude from food handling for 14 days |
Herpes simplex I, II (cold sores / fever blisters) (genital herpes) | Infected secretions HSV I – saliva HSV II – sexual | Tingling prior to fluid- filled blister(s) that recur in the same area (mouth, nose, genitals) | 2-14 days | As long as lesions are present; may be intermittent shedding while asymptomatic | Encourage hand hygiene and age- appropriate STD prevention; do not share personal items; avoid blister secretions | No exclusion necessary |
Impetigo (Impetigo contagiosa) | Direct or indirect contact with lesions and their discharge | Lesions/blisters are generally found on the mouth and nostrils and occasionally near eyes | Variable, usually 4- 10 days, but can be as short as 1-3 days | While sores are draining | Encourage good hand hygiene | Cover lesions; can delay treat until day’s end; no exclusion if treatment started before next day |
Disease | Mode of Spread | Symptoms | Incubation Period | Contagious Period | Contacts | Exclusions (subject to LHD approval) |
*Influenza** (influenza-like illness) | Droplet; contact with respiratory secretions or contaminated surfaces | High fever, fatigue, sore throat, cough, aches, runny nose, headache | 1-4 days | 1 day prior to onset of symptoms to 1 week or more after onset | Exclude with first signs of illness; encourage cough etiquette and good hand hygiene | Exclude until 24hrs with no fever and cough has subsided |
Measles** ⱡ (Rubeola) (Hard/red measles) | Contact with nasal or throat secretions; airborne via sneezing and coughing | High fever, runny nose, cough, red, watery eyes, followed by rash on face, then body | Average 10-12 days (range 7-21 days) from exposure to fever onset | 4 days before to 4 days after rash onset | Exclude contacts lacking documentation of immunity until 21 days after last onset | Cases: Exclude until 4 days after rash onset |
Meningitis** ⱡ (Aseptic/viral) | Varies with causative agent: droplet or fecal oral route; may result from another illness | Severe headache, stiff neck or back, vomiting, fever, light intolerance, neurologic symptoms | Varies with causative agent | Varies with causative agent, but generally 2- 14 days | Encourage cough etiquette and good hand hygiene | Exclude until medically cleared |
Meningitis** ⱡ (Bacterial) (N. meningitis) (H. influenzae) (S. pneumoniae) | Contact with respiratory secretions; spread by sneezing, coughing, and sharing beverages or utensils | Severe headache, fever, stiff neck or back, vomiting, irritability, light sensitivity, rash, neurologic symptoms; | Average 2-4 days (range 1-10 days) | Generally considered no longer contagious after 24hrs of antibiotic treatment | Immediately notify LHD; encourage good hand hygiene; do not share personal items and eating utensils | Medical clearance required; exclude until 24hrs after antimicrobial treatment |
Molloscum contagiosum | Transmitted by skin- to-skin contact and through handling contaminated objects | Smooth, firm, flesh- colored papules (bumps) with an indented center | Usually between 2 and 7 weeks | Unknown but likely as long as lesions persist | Do not share personal items | No exclusion necessary |
Mpox virus (MPV) ⱡ | Close contact (e.g., skin-to-skin); respiratory secretions or surfaces | Rash (several stages, with scabs), fever, chills, swollen lymph nodes, aches, sore throat | 21 days | From onset until the rash has completely healed | Monitor for signs or symptoms and exclude with first signs of illness | Exclude until scabs have fallen off, and a fresh layer of skin has formed (~2-4 weeks) |
Mononucleosis | Person-to-person via saliva | Fever, sore throat, fatigue, swollen lymph nodes, enlarged spleen | 30-50 days | Prolonged, possibly longer than 1 year | Do not share personal items | Exclude until able to tolerate activity; Exclude from contact sports until recovered |
MRSA** (Methicillin-resistant Staphylococcus aureus) | Transmitted by skin- to-skin contact and contact with surfaces that have contacted infection site drainage | Possibly fever; lesion may resemble a spider bite (swollen, draining, painful); asymptomatic carriage is possible | Varies | As long as lesions are draining; found in the environment; good hand hygiene is the best way to avoid infection | Encourage good hand hygiene; do not share personal items such as towels, washcloths, clothing, and uniforms | No exclusion if covered and drainage contained; No swim exclusion if covered by waterproof bandage |
Mumps** ⱡ 
| Airborne or direct contact with saliva | Salivary gland swelling (usually parotid); chills, fever, headache | Average 16-18 days (range 12-25 days) | 7 days prior to and 8 days after parotitis onset | Exclude contacts lacking documentation of immunity until 25 days after last onset | Exclude until 5 days after onset of salivary gland swelling |
Disease | Mode of Spread | Symptoms | Incubation Period | Contagious Period | Contacts | Exclusions (subject to LHD approval) |
*Norovirus** (viral gastroenteritis) | Food, water, surfaces contaminated with vomit or feces, person-to-person, aerosolized vomit | Nausea, vomiting, diarrhea, abdominal pain for 12-72hrs; possibly low-grade fever, chills, headache | Average 24-48hrs (range: 12-72hrs) | Usually from onset until 2-3 days after recovery; typically, virus is no longer shed after 10 days | Encourage good hand hygiene; contact LHD for environmental cleaning recommendations | Exclude until illness has ceased for at least 2 days; exclude from food handling for 3 days after recovery |
Pink Eye (conjunctivitis) | Discharge from eyes, respiratory secretions; from contaminated fingers, shared eye make-up applicators | Bacterial: Often yellow discharge in both eyes Viral: Often one eye with watery/clear discharge and redness Allergic: itchy eyes with watery discharge | Variable but often 1-3 days | During active infection (range: a few days to 2-3 weeks) | Encourage good hand hygiene | Exclude only if herpes simplex conjunctivitis and eye is watering; exclusion also may be necessary if 2 or more children have watery, red eyes; contact LHD |
Poliomyelitis ⱡ (polio)  | Contact with the feces of an infected person (or less often, from respiratory droplets) | Most asymptomatic; 25%: flu-like symptoms e.g., sore throat, fatigue fever, headache; rarely meningitis or paralysis | Nonparalytic: 3-6 days;
Paralysis: usually 7- 21 days | Most risk 7-10 days before / following onset; possible while virus is excreted; Asymptomatic transmission possible. | Exclude contacts lacking documentation of immunity | At least 14 days from onset and until 2 stool samples taken 7 days apart are negative. |
Rash Illness (Unspecified) | Variable depending on causative agent | Skin rash with or without fever | Variable depending on causative agent | Variable depending on causative agent | Variable depending on causative agent | Exclude if fever, change in behavior |
Respiratory Illness (Unspecified) | Contact with respiratory secretions | Fever, sore throat, cough, runny nose | Variable but often 1-3 days | Variable depending on causative agent | Promote hand hygiene and cough etiquette | Exclude until fever free for 24hrs |
Respiratory Syncytial Virus (RSV) | Droplet; contact with respiratory secretions or contaminated surfaces | Fever, sore throat, cough, wheezing, runny nose, sneezing, fever; may appear in stages; may cause bronchiolitis, pneumonia | Average 4-6 days (range: 2-8 days) | Usually 3-8 days, beginning ~ 1 day before onset; infants and immunocompromised people can spread the virus for 3-4 weeks | Promote hand hygiene and cough etiquette | Exclude until fever free for 24hrs. Note: cough often lasts as long as 3 weeks. |
Ringworm (Tinea) | Direct contact with an infected animal, person, or contaminated surface | Round patch of red, dry skin with red raised ring; temporary baldness | Usually 4-14 days | As long as lesions are present and fungal spores exist on materials | Inspect skin for infection; do not share personal items; seek veterinary care for pets with signs of skin disease | Can delay treatment until day’s end; no exclusion if treatment started before next day; exclude from contact sports, swim until treatment start |
Rubella** ⱡ (German Measles) 
| Direct contact; contact with respiratory secretions; airborne (e.g., sneeze) | Red, raised rash for ~3 days; possibly fever, headache, fatigue, red eyes | Average 16-18 days (range: 14-21 days) | 7 days before to 7 days after rash onset | If pregnant, consult OB; exclude contacts lacking documentation of immunity until 21 days after last onset | Exclude until 7 days after onset of rash |
Disease | Mode of Spread | Symptoms | Incubation Period | Contagious Period | Contacts | Exclusions (subject to LHD approval) |
Salmonellosis ⱡ | Fecal-oral: person-to- person, contact with infected animals, or via contaminated food | Abdominal pain, diarrhea (possibly bloody), fever, nausea, vomiting, dehydration | Average 12-36hrs (range: 6hrs-7 days) | During active illness and until organism is no longer detected in feces | Exclude with first signs of illness; encourage good hand hygiene | Exclude until diarrhea has ceased for at least 2 days; additional restrictions may apply |
Scabies | Close, skin-to-skin contact with infected person or via infested clothing or bedding Scabies Prevention and Control Manual | Extreme itching (may be worse at night); mites burrowing in skin cause rash / bumps | 2-6 weeks for first exposure; 1-4 days for re-exposure | Until mites are killed by appropriate treatment; prescription skin and oral medications are generally effective after one treatment | Treat close contacts and infected persons at the same time; avoid skin-to-skin contact; do not share personal items; see exclusions | Treatment may be delayed until end of the day; if treatment started before next day’s return, no exclusion necessary |
Shigellosis** ⱡ | Fecal-oral: frequently person-to-person; also via contaminated food or water | Abdominal pain, diarrhea (possibly bloody), fever, nausea, vomiting, dehydration | Average 1-3 days (range 12-96hrs) | During active illness and until no longer detected; treatment can shorten duration | Exclude with first signs of illness; encourage good hand hygiene | Exclude until diarrhea has ceased for at least 2 days; Medical clearance required |
Strep throat / Scarlet Fever | Respiratory droplet or direct contact; via contaminated food | Sore throat, fever; Scarlet Fever: body rash and red tongue | Average 2-5 days (range 1-7 days) | Until 12hrs after treatment; (10-21 days without treatment) | Exclude with signs of illness; encourage good hand hygiene | Exclude until 12hrs after antimicrobial therapy (2+ doses) |
Streptococcus  pneumoniae ⱡ | Contact with respiratory secretions | Varies: ear infection, pneumonia, meningitis | Varies; as short as 1- 3 days | Until 24hrs after antimicrobial therapy | Consult LHD to discuss any need for treatment | Exclude until 24hrs after antibiotics |
Tuberculosis (TB) ⱡ | Airborne; spread by coughing, sneezing, speaking, or singing | Fever, fatigue, weight loss, cough (3+ weeks), night sweats, anorexia | 2-10 weeks | While actively infectious | Consult LHD to discuss need for evaluation and testing of contacts | Exclude until medically cleared |
Typhoid fever (Salmonella typhi) ⱡ | Fecal-oral: person-to- person, ingestion of contaminated food or water (cases are usually travel-related) | Fever, headache, rose spots, malaise, cough, anorexia, diarrhea, constipation, abd pain, mental status change | Average range: 8-14 days (3-60 days reported) | From first week of illness through convalescence | Consult LHD for evaluation of close contacts | Exclude until symptom free; Medical clearance required; Contact LHD about additional restrictions |
Vomiting Illness (Unspecified) | Varies; See Norovirus | Vomiting, cramps, mild fever, diarrhea, nausea | Varies; See Norovirus | Varies; See Norovirus | Encourage good hand hygiene; See Norovirus | Exclude until 24hrs after last episode |
Whooping Cough** (Pertussis) ⱡ 
| Contact with respiratory secretions | Initially mild respiratory symptoms, cough; may have inspiratory whoop, post-tussive vomiting | Average 7-10 days (range 5-21 days) | With onset of cold-like symptoms until 21 days from onset (or until 5 days of treatment) | Consult LHD to discuss the potential need for treatment | Exclude until 21 days after onset or until 5 days after appropriate antibiotic treatment |
West Nile Virus | Bite from an infected mosquito | High fever, nausea, headache, stiff neck | 3-14 days | Not spread person-to- person | Avoid bites with EPA- approved repellents | No exclusion necessary |
** Urgent healthcare may be necessary; call 911 if an epinephrine auto injector (EpiPen) was administered.
