Here's a list of ways to diagnose at home what's going on, and possible inexpensive ways to help with those issues. Try to handle things as much as you can doing basic things first, but realize when you're outside your limits.

If things get bad, I'll post some links of other things. We're not there yet. This is a repost from where I posted videos on how to do things like percussive therapy.
Thread: GLP How many of us are sick today ?????unidentified respiratory illness?????Post if you cant stop coughing!!!! (Page 18)

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Now that we are officially at epidemic numbers, the best treatment is avoiding public events. Buying supplies so you don't have to go back and get exposed to coughing people. Paying at the gas pump not going inside.

Then you do nasal rinses once a week with clean water that's been boiled and salt added. Then you know it's safer. If the passages are irrigated then they are cleaner. That interferes with germs. Believe me, you will have some germs always, but it's when it overwhelms your system that it's bad.

Yes, boost your immune system when not sick. Exercise. Eat healthy especially now. Load up on antioxidants. Drink clean non-fluridated water. Get proper natural sleep.

If you get sick. Kinda tired been saying this over and over in numerous topics, try:

1. Don't take cough suppressants. You need to expel the mucus. You need an expectorant. Use a cough suppressant at night to get sleep. Avoid menthol, or minimally use it. Menthol while thinning mucus ALSO INCREASES MUCUS PRODUCTION. It's counter-productive. It can clear the sinuses briefly then do a nasal rinse and stop using the menthol. If you wish to do that, try some chinese mustard since it contains horseradish and that also clears the sinuses and doesn't cause more mucus.
2. Use an inhaler and an extender to relax the smooth muscle of the respiratory tract. You are coughing because the mucus is building up to trap the pathogen. See point #1
3. Still do a nasal rinse as above to wash away the infection. If you have a wound, then you clean it first, right?
4. If a patient can't cough up mucus, then do percusive therapy. See my sig or do a GLP search. You tap the shoulders, back, or chest and this mechanically loosens the mucus plug. Then they can cough it up.
5. Don't swallow mucus. Expel it. Swallowed mucus traps food particles and bacteria and believe it or not, mucus then often rises again along the respiratory tract and throat and is reinserted into your nose. You're making yourself sicker. You could get a secondary bacterial infection.
6. If your fever is less that 102 and your mucus is clear, you have a virus. There are few medicines. Tamiflu only shortens the symptom length. If there are shortages, they will limit prescibing it anyway.
7. If your fever is 102+ and your mucus is dark yellow or green, then it contains dying white blood cells. That's what colors mucus. You have a bacterial infection. Get antibiotics.
8. If not feverish, then take warm baths, not showers to increase lymph flow. Often people can go into shock when they get too chilled.
9. Massage the sinuses to push infected material out. Don't give overall massage as it could push the infection towards the heart and organs. A clogged sinus can easily get a bacterial infection and now you have two problems.
10. If vomiting and/or diarrhea (gasteroenteritis), then you need oral rehydrating solution (ORS)to stay hydrated. See my sig on instructions. Many people get sicker because of this.
11. If you are vomiting or have diarrhea is could be Norovirus. Usually that is a LOT of these two. It's usually both. You especially need ORS. Expect the whole family to get it as it is highly contagious.
12. If you have vomiting and respiratory illness, chances are that if your mucus is yellow or green you have a specific bacterial infection called Staph aureus. You need antibiotics. Most "flu" (respiratory illness) doesn't have vomiting.
12a. If someone gets dehydrated, their blood pressure could drop. Raise their legs above their head. They could go into shock. Keep them warm. Prevention is way easier than dealing with this.
13. Take your temperature regularly. Write it down. In fact write down your symptoms. You need to clearly and concisely communicate exactly your symptoms so you get the right medicine.
14. If sick and there are people around, segregate yourself as much as possible and use a mask when outside the room to minimize THEM getting sick. The last thing you need is everyone sick at once.
15. If a young person (typically) has coughing in which they hack and cough and then must suck in air and make a distinctive sound (pertusis or whooping cough) then you need to go right away to the doc for treatment.
16. If a young child or baby can't or won't blow their nose, use a snotsucker. You need to get that out of there, or they will definitely get sicker.
17. If a baby gets sick with clear mucus and wheezes, then most likely they have RSV (viral). You can gently tap and do percussive therapy to dislodge the mucus. Ask if you can do breathing treatments at home. Watch them like a hawk. They can get very weak, can't rouse them, won't eat so fussy, etc. Seek treatment.
18. Don't eat dairy or cut it way back if not a baby on formula. Milk helps create mucus and that is the last thing you want.Milk is largely digested in the intestines so avoided with gasteroenteritis like Norovirus.
19. If nothing will bring up mucus, and it's clear, and you have a dry hacking cough, then you especially need a vaporizer. There are special teas and cough syrup for this. Find one with slippery elm as that sooths the best. Liquorice root too. Both ingredients if you find one. Youcan't use liquorice root is you are on heart medication. Breathe Easy tea and Throat Coat tea are both found in most grocery or drug stores and are great.
20. You can't get strong if you don't eat. Find something you can eat. If you're having trouble keeping food down then eat very small portions.
21. If you have bad diarrhea, most of the time you want to expel it. If it's ridiculous, then use loperimide (Imodium). The generic is far cheaper and the same. It relaxes the spasm.
22.If you have an ear ache, you could easily stumble and fall. Don't let people with ear aches drive or walk around without help. It's very painful. They lose their balance because that sense is developed inside the ear. Falls usually happen when they shower.
23. It's very common for someone to have atypical pneumonia and be misdiagnosed. They most often have clear mucus and a hacking cough. All patients with this have chills and clammy skin and fever. Body aches. People think you don't have pneumonia, but then a chest Xray shows it. Eye pain which is unusual. Shortness of breath when climbing stairs.
23b. Atypical Pneumonia as above but you could have bloody mucus if Legionella is present but that's usually older people.The elderly are often confused. Diarhea not vomiting.

I hope this helps. It's the main points. Do only the part based upon the symptoms. Wouldn't it be smart to print this and refer to it, and so help diagnose when someone gets sick?

If you have a respiratory illness and then your neck hurts, you have the worst headache of your life, eye pain, sensitiveity to light, then seek treatment. It might be viral or bacterial meningitis. You can't treat that at home.