Hi'
Thanks for contecting HCM team
First i would like to say don't worry about 
Dengue. my explanation will help you
Dengue viruses  are the causative agents of dengue fever (DF) and dengue hemorrhagic fever, mosquito-borne flavi viruses and are the causative agents of dengue fever. There is two types of test for dengue is widely used
1 Dengue NS 1 antigen test  - dengue antigen test were able to detect dengue virus infection from Days 1 to 8 .Detection of NS1 during the febrile phase of a primary infection may be greater than 90% sensitive however is only 60–80% in subsequent infections. It early detection test and his test  is positive.
2. Dengue 
antibodies Ig G & Ig M are specific test but can be perform after 7 days of onset of disease because antibodies are produce after 5 - 7 days.IgG, b remains detectable for over 60 years and, in the absence of symptoms, is a useful indicator of past infection.
Dengue is detected early in your husband's case so it is positive in NS1 and negative in antibody test.
 Watch upon Vitals Blood presure, Pulse regularly thrice minimum in a day.
observed upon his 
Platelet count and PCV( hematocrite) TWICE on daily basis if platelet count Falls below 40,000 immediate contact to your treating Physician
OBSERVED upon bleeding from gum nasal or any site.
TREATMENT DENGUE 
Dengue is 
viral fever and NO SPECIFIC ANTI VIRAL FOR IT only platelet transfusion is option to correct platelet 
Those who are able to drink, are passing urine, have no "warning signs" and are otherwise healthy can be managed at home with daily follow up and oral rehydration therapy.Those who have other health problems, have "warning signs" or who cannot manage regular follow up should be cared for in hospital. 
 Oral rehydration therapy means take WHO recommended ORS . Panalty of Oral fluid. Some natural therapy like Fresh Coconut water ( Not in concentrated or Juice Form) will help to increased self immune system
When Platelet count falls bellow 20,000 needs platelet transfusion and prefer Single Donor apheresis platelet ( will helps 30,000to 70000 platelet in single transfusion.
Use mouth wash no brush to prevent Gum bleeding.
KEEP REGULAR CONTACT WITH YOUR DOCTOR 
Take complete bed rest
DOLO 650 IS OK TO PREVENT FEVER AVOID PAIN KILLER AND TAKE MEDICINE ONLY EXPERT ADVISE BY PHYSICIAN   
 I need your 
salmonella typhi titers count , which will help me for diagnosis of 
typhoid.