Causes of Upper respiratory infections and drug therapy

• Enteroviruses: A large group of viruses that can cause various illnesses, including some common colds.

Less commonly, bacteria can cause URIs, particularly as secondary infections following a viral illness. Examples include:

• Streptococcus pyogenes (Group A Streptococcus): The cause of strep throat, a bacterial infection of the pharynx.
• Haemophilus influenzae: Can cause sinusitis and ear infections.
• Moraxella catarrhalis: Another bacterial cause of sinusitis and ear infections.

Drug Therapy for URIs:

It's important to note that antibiotics are generally ineffective against viral URIs, which constitute the majority of cases. Inappropriate antibiotic use contributes to antibiotic resistance, a significant global health concern.

Drug therapy for viral URIs primarily focuses on symptom relief:

• Analgesics and Antipyretics:
  • Acetaminophen (Paracetamol): Effective for reducing fever and mild to moderate pain (headache, muscle aches, sore throat). Widely available in Kisumu and Kenya.
  • Ibuprofen: Another NSAID (non-steroidal anti-inflammatory drug) that helps reduce fever, pain, and inflammation.
• Decongestants:
  • Oral Decongestants (e.g., Pseudoephedrine, Phenylephrine): Help relieve nasal congestion by constricting blood vessels in the nasal passages. May have side effects like increased heart rate and blood pressure, so caution is advised, especially for individuals with hypertension or heart conditions. Pseudoephedrine may have restricted availability in some regions due to its potential use in illicit drug manufacturing.
  • Nasal Decongestant Sprays (e.g., Oxymetazoline, Xylometazoline): Provide rapid relief from nasal congestion but should only be used for a limited duration (typically 3-5 days) to avoid rebound congestion.
• Antihistamines:
  • First-generation antihistamines (e.g., Chlorpheniramine, Diphenhydramine): Can help with runny nose and sneezing but often cause drowsiness.
  • Second-generation antihistamines (e.g., Loratadine, Cetirizine): Less likely to cause drowsiness and are often preferred for daytime use if allergic rhinitis symptoms are present or suspected to be contributing to the URI.
• Cough Suppressants (Antitussives):
  • Dextromethorphan: Helps to suppress a dry, non-productive cough.
  • Codeine: A stronger cough suppressant, usually requiring a prescription and may have side effects like constipation and drowsiness. Not typically a first-line treatment for common cold coughs.
• Expectorants (e.g., Guaifenesin): Aim to thin mucus, making it easier to cough up. Evidence for their effectiveness is somewhat limited.
• Sore Throat Remedies:
  • Lozenges and throat sprays: Can provide temporary relief from sore throat pain.
  • Warm salt water gargles: A simple and often effective home remedy for soothing a sore throat.

Bacterial URIs (e.g., Strep Throat, Bacterial Sinusitis):

If a bacterial infection is diagnosed (usually through a throat swab for strep throat or clinical assessment for bacterial sinusitis), antibiotics are the appropriate treatment. The specific antibiotic prescribed will depend on the type of bacteria identified and local resistance patterns. Common antibiotics used for bacterial URIs include:

• Penicillin or Amoxicillin: For strep throat.
• Amoxicillin-clavulanate: For bacterial sinusitis or ear infections.
• Macrolides (e.g., Azithromycin, Clarithromycin): As alternatives for penicillin-allergic patients.

It is crucial for patients in Kisumu and elsewhere to seek medical advice for suspected bacterial URIs and to complete the full course of antibiotics as prescribed to ensure eradication of the bacteria and prevent complications. Self-treating with leftover antibiotics is strongly discouraged due to the risk of contributing to antibiotic resistance.

2. Discuss Triggers of Asthma and Treatment Options

Asthma is a chronic respiratory disease characterized by inflammation and narrowing of the airways, leading to recurrent episodes of wheezing, shortness of breath, chest tightness, and coughing. These symptoms are often triggered by various environmental and internal factors.  

Triggers of Asthma:

Asthma triggers are diverse and can vary significantly from person to person. Common triggers include:

• Allergens:
  • Indoor allergens: Dust mites, pet dander (especially from cats and dogs), mold spores. These are relevant in Kisumu homes as well.
  • Outdoor allergens: Pollen from trees, grasses, and weeds. Seasonal variations in pollen counts can trigger asthma attacks.
  • Cockroaches: A common household allergen, particularly in urban environments like Kisumu.
• Irritants:
  • Air pollution: Smoke (from burning wood, charcoal, or traffic), fumes, strong odors (perfumes, cleaning products), chemical irritants. Air quality can be a concern in urban areas.
  • Tobacco smoke: Active and passive smoking are major asthma triggers and worsen overall lung health.
  • Cold air and changes in weather: Sudden shifts in temperature or humidity can trigger bronchospasm.
• Respiratory Infections: Viral infections like the common cold or influenza are frequent triggers for asthma exacerbations.
• Exercise: Exercise-induced bronchoconstriction (EIB) occurs in many people with asthma, especially in cold, dry air.
• Emotions: Strong emotions like stress, anxiety, excitement, or laughter can sometimes trigger asthma symptoms.
• Certain Medications: Non-steroidal anti-inflammatory drugs (NSAIDs) like aspirin and ibuprofen, and beta-blockers can trigger asthma in some individuals.
• Food Additives and Preservatives: Sulfites found in some foods and beverages can trigger asthma in sensitive individuals.
• Gastroesophageal Reflux Disease (GERD): Stomach acid refluxing into the esophagus can irritate the airways and worsen asthma symptoms.

Identifying and avoiding individual asthma triggers is a crucial part of managing the condition. This often involves allergy testing and careful observation of symptom patterns.

Treatment Options for Asthma:

Asthma treatment aims to control symptoms, prevent exacerbations (attacks), and maintain good lung function. It typically involves a combination of medications and lifestyle management.

1. Medications:

• Long-Term Control Medications (Preventers): Taken daily to reduce airway inflammation and prevent symptoms.
  • Inhaled Corticosteroids (ICS): The cornerstone of long-term asthma control (e.g., Beclomethasone, Budesonide, Fluticasone). They reduce inflammation in the airways.
  • Long-Acting Beta2-Agonists (LABAs): Relax the muscles around the airways, helping to open them up (e.g., Salmeterol, Formoterol). LABAs are always used in combination with ICS and should not be used alone due to an increased risk of severe asthma exacerbations. Combination inhalers containing both ICS and LABA are common.
  • Leukotriene Modifiers: Block the action of leukotrienes, inflammatory chemicals that contribute to asthma symptoms (e.g., Montelukast, Zafirlukast). Usually taken orally.
  • Long-Acting Muscarinic Antagonists (LAMAs): Another class of bronchodilators that can be added for more severe asthma (e.g., Tiotropium).
  • Biologics: For severe allergic asthma or eosinophilic asthma that is not well-controlled with other medications (e.g., Omalizumab, Mepolizumab, Reslizumab, Benralizumab, Dupilumab). These are injectable medications that target specific inflammatory pathways. Access to biologics may be limited in some settings.
• Quick-Relief Medications (Rescue Medications): Used to quickly relieve acute asthma symptoms.
  • Short-Acting Beta2-Agonists (SABAs): Relax the muscles around the airways rapidly (e.g., Salbutamol/Albuterol). These are essential for treating acute asthma attacks. They are often administered via inhalers or nebulizers.
  • Oral Corticosteroids (OCS): Such as Prednisone, are sometimes needed for severe asthma exacerbations to reduce inflammation quickly. They are typically used for short courses due to potential side effects.
  • Anticholinergics: Ipratropium bromide can also be used as a quick-relief medication, particularly in combination with SABAs for more severe attacks.

2. Other Treatment Options and Management:

• Asthma Action Plan: A written plan developed with a healthcare provider that outlines daily management, how to recognize worsening symptoms, and when to use rescue medications and seek medical help.
• Trigger Avoidance: Identifying and minimizing exposure to individual asthma triggers is crucial.
• Allergy Management: If allergies are a trigger, strategies like allergen avoidance, antihistamines, or allergy immunotherapy (allergy shots) may be recommended.

1. Causes of Upper Respiratory Infections (URIs) and Drug Therapy

Upper respiratory infections (URIs), also known as the common cold, are infections of the upper respiratory tract, which includes the nose, sinuses, pharynx (throat), and larynx (voice box). They are extremely common, especially during colder months.

Causes of URIs:

The vast majority of URIs are caused by viruses. The most common culprits include:

• Rhinoviruses: These are the most frequent cause of the common cold. There are many different serotypes, which is why we can get colds repeatedly.
• Coronaviruses: While some coronaviruses cause severe respiratory illnesses like COVID-19, others are responsible for milder common colds.
• Respiratory Syncytial Virus (RSV): Primarily affects young children and infants but can also cause milder illness in older individuals.
• Parainfluenza Viruses: These viruses can cause a range of respiratory illnesses, including croup in children and cold-like symptoms in adults.
• Adenoviruses: Can cause a variety of symptoms, including colds, sore throat, conjunctivitis, and even gastrointestinal issues.