There is low or very-low quality evidence that probiotics may be better than placebo in preventing acute URTIs. Vaccination against influenza viruses, adenoviruses, measles, rubella, "Streptococcus pneumoniae", "Haemophilus influenzae", diphtheria, "Bacillus anthracis", and "Bordetella pertussis" may prevent them from infecting the URT or reduce the severity of the infection.

Treatment is often supportive in nature, and depends on the severity and type of laryngitis (acute or chronic). General measures to relieve symptoms of laryngitis include behaviour modification, hydration and humidification.

Vocal hygiene (care of the voice) is very important to relieve symptoms of laryngitis. Vocal hygiene involves measures such as

- Resting the voice

- Drinking sufficient amounts of water

- Reducing caffeine and alcohol intake

- Stopping smoking

- Limiting throat clearing

Voice hygiene programs are given by speech-language pathologists. These programs typically include the following components:

- Addressing amount and type of voice use

- Reducing behaviours that are damaging to the vocal folds

- Increasing hydration

- Adjusting lifestyle (for example, limiting caffeine and managing medical conditions)

In general, acute laryngitis treatment involves vocal hygiene, painkillers (analgesics), humidification, and antibiotics.

The Centers for Disease Control describe protocol for treating sinusitis while at the same time discouraging overuse of antibiotics:

- Target likely organisms with first-line drugs: Amoxicillin, Amoxicillin/Clavulanate

- Use shortest effective course: Should see improvement in 2–3 days. Continue treatment for 7 days after symptoms improve or resolve (usually a 10–14 day course).

- Consider imaging studies in recurrent or unclear cases: some sinus involvement is frequent early in the course of uncomplicated viral URI

Treatment comprises symptomatic support usually via analgesics for headache, sore throat and muscle aches. Moderate exercise in sedentary subjects with naturally acquired URTI probably does not alter the overall severity and duration of the illness. No randomized trials have been conducted to ascertain benefits of increasing fluid intake.

Many cases of croup have been prevented by immunization for influenza and diphtheria. At one time, croup referred to a diphtherial disease, but with vaccination, diphtheria is now rare in the developed world.

The majority of cases of throat irritation usually go away without any treatment. There is no real treatment for throat irritation from a virus. If you have difficulty swallowing then one should drink liquids, suck on lozenges, ice chips or mix salt with warm water to gargle. Bacterial infections generally require antibiotics.

Home remedies for throat irritation include gargling with warm water twice a day, sipping honey and lemon mixture or sucking on medicated lozenges. If the cause is dry air, then one should humidify the home. Since smoke irritates the throat, stop smoking and avoid all fumes from chemicals, paints and volatile liquids.

Rest your voice if you have been screaming or singing. If you have pharyngitis, avoid infecting others by covering your mouth when coughing and wear a mask.

Corticosteroids, such as dexamethasone and budesonide, have been shown to improve outcomes in children with all severities of croup. Significant relief is obtained as early as six hours after administration. While effective when given by injection, or by inhalation, giving the medication by mouth is preferred. A single dose is usually all that is required, and is generally considered to be quite safe. Dexamethasone at doses of 0.15, 0.3 and 0.6 mg/kg appear to be all equally effective.

Post-viral cough can be resistant to treatment. Post-viral cough usually goes away on its own; however, cough suppressants containing codeine may be prescribed. A study has claimed theobromine in dark chocolate is more effective.

In cases of viral adenoiditis, treatment with analgesics or antipyretics is often sufficient. Bacterial adenoiditis may be treated with antibiotics, such as amoxicillin - clavulanic acid or a cephalosporin. In case of adenoid hypertrophy, adenoidectomy may be performed to remove the adenoid.

Adenoiditis occurs mainly in childhood, often associated with acute tonsillitis. Incidence decreases with age, with adenoiditis being rare in children over 15 years due to physiological atrophy of the adenoid tissue.

The best prevention against viral pneumonia is vaccination against influenza, adenovirus, chickenpox, herpes zoster, measles, and rubella.

Most household disinfectants will inactivate FHV-1. The virus can survive up to 18 hours in a damp environment, but less in a dry environment and only shortly as an aerosol.

There is a vaccine for FHV-1 available (ATCvet code: , plus various combination vaccines), but although it limits or weakens the severity of the disease and may reduce viral shedding, it does not prevent infection with FVR. Studies have shown a duration of immunity of this vaccine to be at least three years. The use of serology to demonstrate circulating antibodies to FHV-1 has been shown to have a positive predictive value for indicating protection from this disease.

In cases of viral pneumonia where influenza A or B are thought to be causative agents, patients who are seen within 48 hours of symptom onset may benefit from treatment with oseltamivir or zanamivir. Respiratory syncytial virus (RSV) has no direct acting treatments, but ribavirin in indicated for severe cases. Herpes simplex virus and varicella-zoster virus infections are usually treated with aciclovir, whilst ganciclovir is used to treat cytomegalovirus. There is no known efficacious treatment for pneumonia caused by SARS coronavirus, MERS coronavirus, adenovirus, hantavirus, or parainfluenza. Care is largely supportive.

Viruses are common causes of the common cold. Less often, bacteria may also cause pharyngitis. Both of these organisms enter the body via the nose or mouth as aerosolized particles when someone sneezes or coughs. Because many germs are contagious, one can even acquire them from touching utensils, toys, personal care products or door knobs. The most common viruses that causes throat irritation include the common cold virus, influenza, infectious mononucleosis, measles and croup. Most bacteria and viruses usually induce throat irritation during the winter or autumn.

One possible cause for post-viral cough is that the receptors that are responsible for stimulating the cough during the respiratory tract infection are up-regulated by respiratory tract infection and continue to stimulate even after the virus has disappeared.

Vaccination helps prevent bronchopneumonia, mostly against influenza viruses, adenoviruses, measles, rubella, streptococcus pneumoniae, haemophilus influenzae, diphtheria, bacillus anthracis, chickenpox, and bordetella pertussis.

Antibiotics do not help the many lower respiratory infections which are caused by parasites or viruses. While acute bronchitis often does not require antibiotic therapy, antibiotics can be given to patients with acute exacerbations of chronic bronchitis. The indications for treatment are increased dyspnoea, and an increase in the volume or purulence of the sputum. The treatment of bacterial pneumonia is selected by considering the age of the patient, the severity of the illness and the presence of underlying disease. Amoxicillin and doxycycline are suitable for many of the lower respiratory tract infections seen in general practice.

Normal surgical masks and N95 masks appear equivalent with respect to preventing respiratory infections.

Antivirals such as acyclovir, famciclovir, or valacyclovir may be used. Intravenous acyclovir is reserved for individuals who cannot swallow due to the pain, individuals with other systemic manifestations of herpes or severely immunocompromised individuals.

Despite decades of research, no vaccines currently exist.

Recombinant technology has however been used to target the formation of vaccines for HPIV-1, -2 and -3 and has taken the form of several live-attenuated intranasal vaccines. Two vaccines in particular were found to be immunogenic and well tolerated against HPIV-3 in phase I trials. HPIV-1 and -2 vaccine candidates remain less advanced.

Vaccine techniques which have been used against HPIVs are not limited to intranasal forms, but also viruses attenuated by cold passage, host range attenuation, chimeric construct vaccines and also introducing mutations with the help of reverse genetics to achieve attenuation.

Maternal antibodies may offer some degree of protection against HPIVs during the early stages of life via the colostrum in breast milk.

Parainfluenza viruses last only a few hours in the environment and are inactivated by soap and water. Furthermore, the virus can also be easily destroyed using common hygiene techniques and detergents, disinfectants and antiseptics.

Environmental factors which are important for HPIV survival are pH, humidity, temperature and the medium the virus in found within. The optimal pH is around the physiologic pH values (7.4 to 8.0), whilst at high temperatures (above 37 °C) and low humidity, infectivity reduces.

The majority of transmission has been linked to close contact, especially in nosocomial infections. Chronic care facilities and doctors' surgeries are also known to be transmission 'hotspots' with transmission occurring via aerosols, large droplets and also fomites (contaminated surfaces).

The exact infectious dose remains unknown.

Herpes simplex virus is commonly found in humans, yet uncommonly results in systemic manifestations. Suppression of HIV with antiretroviral medications, careful monitoring of immunosuppressive medications are important means of prevention. Antiviral prophylaxis such as daily acyclovir in immunocompromised individuals may be considered.

A 2014 systematic review of clinical trials does not support using routine rapid viral testing to decrease antibiotic use for children in emergency departments. It is unclear if rapid viral testing in the emergency department for children with acute febrile respiratory infections reduces the rates of antibiotic use, blood testing, or urine testing. The relative risk reduction of chest x-ray utilization in children screened with rapid viral testing is 77% compared with controls. In 2013 researchers developed a breath tester that can promptly diagnose lung infections.

Prevention of bronchiolitis relies strongly on measures to reduce the spread of the viruses that cause respiratory infections (that is, handwashing, and avoiding exposure to those symptomatic with respiratory infections). In addition to good hygiene an improved immune system is a great tool for prevention. One way to improve the immune system is to feed the infant with breast milk, especially during the first month of life. Immunizations are available for premature infants who meet certain criteria (some cardiac and respiratory disorders) such as Palivizumab (a monoclonal antibody against RSV). Passive immunization therapy requires monthly injections during winter.